1
|
Jałochowski M, Krawiec M, Kwapiński T. Implementation of the Su-Schrieffer-Heeger Model in the Self-Assembly Si-In Atomic Chains on the Si(553)-Au Surface. ACS NANO 2024; 18:12861-12869. [PMID: 38712346 PMCID: PMC11112750 DOI: 10.1021/acsnano.4c00225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 04/11/2024] [Accepted: 04/24/2024] [Indexed: 05/08/2024]
Abstract
Indium-decorated Si atomic chains on a stepped Si(553)-Au substrate are proposed as an extended Su-Schrieffer-Heeger (SSH) model, revealing topological end states. An appropriate amount of In atoms on the Si(553)-Au surface induce the self-assembly formation of trimer SSH chains, where the chain unit cell comprises one In atom and two Si atoms, confirmed by scanning tunneling microscopy images and density functional calculations. The electronic structure of the system, examined through scanning tunneling spectroscopy, manifests three electron bands within the Si-In chain, accompanied by additional midgap topological states exclusively appearing at the chain's end atoms. To elucidate the emergence of these topological states, a tight-binding model for a finite-length-extended SSH chain is proposed. Analysis of the energy spectra, density of states functions, and eigenfunctions demonstrates the topological nature of these self-assembled atomic chains.
Collapse
Affiliation(s)
| | - Mariusz Krawiec
- Institute of Physics, Maria
Curie-Sklodowska University, Lublin 20-031, Poland
| | - Tomasz Kwapiński
- Institute of Physics, Maria
Curie-Sklodowska University, Lublin 20-031, Poland
| |
Collapse
|
2
|
Jałochowski M, Kwapiński T. Distribution of Electron Density in Self-Assembled One-Dimensional Chains of Si Atoms. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6044. [PMID: 37687737 PMCID: PMC10488472 DOI: 10.3390/ma16176044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 08/29/2023] [Accepted: 08/30/2023] [Indexed: 09/10/2023]
Abstract
Scanning tunneling microscopy measurements of height profiles, along the chains of Si atoms on the terrace edges of a perfectly ordered Si(553)-Au surface, reveal an STM bias-dependent mixed periodicity with periods of one, two and one and a half lattice constants. The simple linear chain model usually observed with STM cannot explain the unexpected fractional periodicity in the height profile. It was found that the edge Si chain stands for, in fact, a zigzag structure, which is composed of two neighboring rows of Si atoms and was detected in the STM experiments. Tight-binding calculations of the local density of states and charge occupancy along the chain explain the voltage-dependent modulations of the STM profiles and show that oscillation periods are determined mainly by the surface and STM tip Fermi energies.
Collapse
|
3
|
Do E, Park JW, Stetsovych O, Jelinek P, Yeom HW. Z3 Charge Density Wave of Silicon Atomic Chains on a Vicinal Silicon Surface. ACS NANO 2022; 16:6598-6604. [PMID: 35427105 PMCID: PMC9046978 DOI: 10.1021/acsnano.2c00972] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
An ideal one-dimensional electronic system is formed along atomic chains on Au-decorated vicinal silicon surfaces, but the nature of its low-temperature phases has been puzzling for last two decades. Here, we unambiguously identify the low-temperature structural distortion of this surface using high-resolution atomic force microscopy and scanning tunneling microscopy. The most important structural ingredient of this surface, the step-edge Si chains, are found to be strongly buckled, every third atom down, forming trimer unit cells. This observation is consistent with the recent model of rehybridized dangling bonds and rules out the antiferromagnetic spin ordering proposed earlier. The spectroscopy and electronic structure calculation indicate a charge density wave insulator with a Z3 topology, making it possible to exploit topological phases and excitations. The tunneling current was found to substantially lower the energy barrier between three degenerate CDW states, which induces a dynamically fluctuating CDW at very low temperature.
Collapse
Affiliation(s)
- Euihwan Do
- Center
for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang 37673, Republic of Korea
- Department
of Physics, Pohang University of Science
and Technology (POSTECH), Pohang 37673, Republic of Korea
| | - Jae Whan Park
- Center
for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang 37673, Republic of Korea
| | - Oleksandr Stetsovych
- Institute
of Physics of the Czech Academy of Sciences, Cukrovarnicka 10, 18221 Prague 6, Czech Republic
| | - Pavel Jelinek
- Institute
of Physics of the Czech Academy of Sciences, Cukrovarnicka 10, 18221 Prague 6, Czech Republic
| | - Han Woong Yeom
- Center
for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang 37673, Republic of Korea
- Department
of Physics, Pohang University of Science
and Technology (POSTECH), Pohang 37673, Republic of Korea
| |
Collapse
|
4
|
Park JW, Do E, Shin JS, Song SK, Stetsovych O, Jelinek P, Yeom HW. Creation and annihilation of mobile fractional solitons in atomic chains. NATURE NANOTECHNOLOGY 2022; 17:244-249. [PMID: 34934195 PMCID: PMC8930762 DOI: 10.1038/s41565-021-01042-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 11/02/2021] [Indexed: 06/04/2023]
Abstract
Localized modes in one-dimensional (1D) topological systems, such as Majonara modes in topological superconductors, are promising candidates for robust information processing. While theory predicts mobile integer and fractional topological solitons in 1D topological insulators, experiments so far have unveiled immobile, integer solitons only. Here we observe fractionalized phase defects moving along trimer silicon atomic chains formed along step edges of a vicinal silicon surface. By means of tunnelling microscopy, we identify local defects with phase shifts of 2π/3 and 4π/3 with their electronic states within the band gap and with their motions activated above 100 K. Theoretical calculations reveal the topological soliton origin of the phase defects with fractional charges of ±2e/3 and ±4e/3. Additionally, we create and annihilate individual solitons at desired locations by current pulses from the probe tip. Mobile and manipulable topological solitons may serve as robust, topologically protected information carriers in future information technology.
Collapse
Affiliation(s)
- Jae Whan Park
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang, Korea
| | - Euihwan Do
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang, Korea
- Department of Physics, Pohang University of Science and Technology, Pohang, Korea
| | - Jin Sung Shin
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang, Korea
- Department of Physics, Pohang University of Science and Technology, Pohang, Korea
| | - Sun Kyu Song
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang, Korea
| | | | - Pavel Jelinek
- Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Han Woong Yeom
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang, Korea.
- Department of Physics, Pohang University of Science and Technology, Pohang, Korea.
| |
Collapse
|
5
|
Mamiyev Z, Tegenkamp C, Pfnür H. Plasmon localization by adatoms in gold atomic wires on Si(775). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:205001. [PMID: 33784647 DOI: 10.1088/1361-648x/abf37e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 03/30/2021] [Indexed: 06/12/2023]
Abstract
Self-organized gold chains on vicinal Si(111) surfaces represent prototype examples of quasi-one-dimensional objects that are stabilized by hybridization with Si surface states. Their plasmons contain important information about the unoccupied bandstructure close to the Fermi level. Using Si(775)-Au as an example, we report here the modifications of the plasmon dispersion by the simple atomic adatom species H and O. Using a combination of low energy electron diffraction and high-resolution electron energy loss spectroscopy, we study the interconnection between plasmonic excitation and the corresponding local surface structure. Both adsorbates do not destroy metallicity, but, similar to Si(553)-Au, atomic hydrogen enhances dimerization of the Au chains, which at small concentrations counteracts the disorder introduced by random adsorption. This effect, most likely caused by electron donation of H to the surface states, is missing in case of adsorbed oxygen, so that only the effect of disorder is observed. For both adsorbates increasing disorder as a function of adsorbate concentration finally results in plasmon localization and opening of a band gap.
Collapse
Affiliation(s)
- Z Mamiyev
- Institut für Festkörperphysik, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover, Germany
- Laboratorium für Nano- und Quantenengineering (LNQE), Leibniz Universität Hannover, Schneiderberg 39, 30167 Hannover, Germany
- Institut für Physik, Technische Universität Chemnitz, Reichenhainer Str. 70, D-09126 Chemnitz, Germany
| | - C Tegenkamp
- Institut für Festkörperphysik, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover, Germany
- Laboratorium für Nano- und Quantenengineering (LNQE), Leibniz Universität Hannover, Schneiderberg 39, 30167 Hannover, Germany
- Institut für Physik, Technische Universität Chemnitz, Reichenhainer Str. 70, D-09126 Chemnitz, Germany
| | - H Pfnür
- Institut für Festkörperphysik, Leibniz Universität Hannover, Appelstraße 2, 30167 Hannover, Germany
- Laboratorium für Nano- und Quantenengineering (LNQE), Leibniz Universität Hannover, Schneiderberg 39, 30167 Hannover, Germany
| |
Collapse
|
6
|
Braun C, Neufeld S, Gerstmann U, Sanna S, Plaickner J, Speiser E, Esser N, Schmidt WG. Vibration-Driven Self-Doping of Dangling-Bond Wires on Si(553)-Au Surfaces. PHYSICAL REVIEW LETTERS 2020; 124:146802. [PMID: 32338960 DOI: 10.1103/physrevlett.124.146802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 02/21/2020] [Indexed: 06/11/2023]
Abstract
Density-functional theory is used to explore the Si(553)-Au surface dynamics. Our study (i) reveals a complex two-stage order-disorder phase transition where with rising temperature first the ×3 order along the Si step edges and, subsequently, the ×2 order of the Au chains is lost, (ii) identifies the transient modification of the electron chemical potential during soft Au chain vibrations as instrumental for disorder at the step edge, and (iii) shows that the transition leads to a self-doping of the Si dangling-bond wire at the step edge. The calculations are corroborated by Raman measurements of surface phonon modes and explain previous electron diffraction, scanning tunneling microscopy, and surface transport data.
Collapse
Affiliation(s)
- C Braun
- Lehrstuhl für Theoretische Materialphysik, Universität Paderborn, 33095 Paderborn, Germany
| | - S Neufeld
- Lehrstuhl für Theoretische Materialphysik, Universität Paderborn, 33095 Paderborn, Germany
| | - U Gerstmann
- Lehrstuhl für Theoretische Materialphysik, Universität Paderborn, 33095 Paderborn, Germany
| | - S Sanna
- Institut für Theoretische Physik and Center for Materials Research, Justus-Liebig-Universität Gießen, 35392 Gießen, Germany
| | - J Plaickner
- Leibniz-Institut für Analytische Wissenschaften -ISAS- e.V. Schwarzschildstr. 8, 12489 Berlin, Germany
| | - E Speiser
- Leibniz-Institut für Analytische Wissenschaften -ISAS- e.V. Schwarzschildstr. 8, 12489 Berlin, Germany
| | - N Esser
- Leibniz-Institut für Analytische Wissenschaften -ISAS- e.V. Schwarzschildstr. 8, 12489 Berlin, Germany
- Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstr. 36, 10623 Berlin, Germany
| | - W G Schmidt
- Lehrstuhl für Theoretische Materialphysik, Universität Paderborn, 33095 Paderborn, Germany
| |
Collapse
|
7
|
Hafke B, Brand C, Witte T, Sothmann B, Horn-von Hoegen M, Erwin SC. Thermally Induced Crossover from 2D to 1D Behavior in an Array of Atomic Wires: Silicon Dangling-Bond Solitons in Si(553)-Au. PHYSICAL REVIEW LETTERS 2020; 124:016102. [PMID: 31976688 DOI: 10.1103/physrevlett.124.016102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Indexed: 06/10/2023]
Abstract
The self-assembly of submonolayer amounts of Au on the densely stepped Si(553) surface creates an array of closely spaced "atomic wires" separated by 1.5 nm. At low temperature, charge transfer between the terraces and the row of silicon dangling bonds at the step edges leads to a charge-ordered state within the row of dangling bonds with ×3 periodicity. Interactions between the dangling bonds lead to their ordering into a fully two-dimensional (2D) array with centered registry between adjacent steps. We show that as the temperature is raised, soliton defects are created within each step edge. The concentration of solitons rises with increasing temperature and eventually destroys the 2D order by decoupling the step edges, reducing the effective dimensionality of the system to 1D. This crossover from higher to lower dimensionality is unexpected and, indeed, opposite to the behavior in other systems.
Collapse
Affiliation(s)
- B Hafke
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - C Brand
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - T Witte
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - B Sothmann
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - M Horn-von Hoegen
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - S C Erwin
- Center for Computational Materials Science, Naval Research Laboratory, Washington, D.C. 20375, USA
| |
Collapse
|
8
|
Hogan C, Speiser E, Chandola S, Suchkova S, Aulbach J, Schäfer J, Meyer S, Claessen R, Esser N. Controlling the Local Electronic Properties of Si(553)-Au through Hydrogen Doping. PHYSICAL REVIEW LETTERS 2018; 120:166801. [PMID: 29756924 DOI: 10.1103/physrevlett.120.166801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 11/12/2017] [Indexed: 06/08/2023]
Abstract
We propose a quantitative and reversible method for tuning the charge localization of Au-stabilized stepped Si surfaces by site-specific hydrogenation. This is demonstrated for Si(553)-Au as a model system by combining density functional theory simulations and reflectance anisotropy spectroscopy experiments. We find that controlled H passivation is a two-step process: step-edge adsorption drives excess charge into the conducting metal chain "reservoir" and renders it insulating, while surplus H recovers metallic behavior. Our approach illustrates a route towards microscopic manipulation of the local surface charge distribution and establishes a reversible switch of site-specific chemical reactivity and magnetic properties on vicinal surfaces.
Collapse
Affiliation(s)
- C Hogan
- Istituto di Struttura della Materia-CNR (ISM-CNR), via Fosso del Cavaliere 100, 00133 Rome, Italy
- Dipartimento di Fisica, Università di Roma "Tor Vergata", Via della Ricerca Scientifica 1, 00133 Roma, Italy
| | - E Speiser
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Schwarzschildstraße 8, 12489 Berlin, Germany
| | - S Chandola
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Schwarzschildstraße 8, 12489 Berlin, Germany
| | - S Suchkova
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Schwarzschildstraße 8, 12489 Berlin, Germany
| | - J Aulbach
- Physikalisches Institut and Röntgen Center for Complex Material Systems (RCCM), Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - J Schäfer
- Physikalisches Institut and Röntgen Center for Complex Material Systems (RCCM), Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - S Meyer
- Physikalisches Institut and Röntgen Center for Complex Material Systems (RCCM), Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - R Claessen
- Physikalisches Institut and Röntgen Center for Complex Material Systems (RCCM), Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - N Esser
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Schwarzschildstraße 8, 12489 Berlin, Germany
| |
Collapse
|
9
|
Dudy L, Aulbach J, Wagner T, Schäfer J, Claessen R. One-dimensional quantum matter: gold-induced nanowires on semiconductor surfaces. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:433001. [PMID: 28915127 DOI: 10.1088/1361-648x/aa852a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Interacting electrons confined to only one spatial dimension display a wide range of unusual many-body quantum phenomena, ranging from Peierls instabilities to the breakdown of the canonical Fermi liquid paradigm to even unusual spin phenomena. The underlying physics is not only of tremendous fundamental interest, but may also have bearing on device functionality in future micro- and nanoelectronics with lateral extensions reaching the atomic limit. Metallic adatoms deposited on semiconductor surfaces may form self-assembled atomic nanowires, thus representing highly interesting and well-controlled solid-state realizations of such 1D quantum systems. Here we review experimental and theoretical investigations on a few selected prototypical nanowire surface systems, specifically Ge(0 0 1)-Au and Si(hhk)-Au, and the search for 1D quantum states in them. We summarize the current state of research and identify open questions and issues.
Collapse
Affiliation(s)
- L Dudy
- Physikalisches Institut and Röntgen Center for Complex Material Systems (RCCM), Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | | | | | | | | |
Collapse
|
10
|
Komsa HP, Senga R, Suenaga K, Krasheninnikov AV. Structural Distortions and Charge Density Waves in Iodine Chains Encapsulated inside Carbon Nanotubes. NANO LETTERS 2017; 17:3694-3700. [PMID: 28548839 DOI: 10.1021/acs.nanolett.7b00969] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Atomic chains are perfect systems for getting fundamental insights into the electron dynamics and coupling between the electronic and ionic degrees of freedom in one-dimensional metals. Depending on the band filling, they can exhibit Peierls instabilities (or charge density waves), where equally spaced chain of atoms with partially filled band is inherently unstable, exhibiting spontaneous distortion of the lattice that further leads to metal-insulator transition in the system. Here, using high-resolution scanning transmission electron microscopy, we directly image the atomic structures of a chain of iodine atoms confined inside carbon nanotubes. In addition to long equidistant chains, the ones consisting of iodine dimers and trimers were also observed, as well as transitions between them. First-principles calculations reproduce the experimentally observed bond lengths and lattice constants, showing that the ionic movement is largely unconstrained in the longitudinal direction, while naturally confined by the nanotube in the lateral directions. Moreover, the trimerized chain bears the hallmarks of a charge density wave. The transition is driven by changes in the charge transfer between the chain and the nanotube and is enabled by the charge compensation and additional screening provided by the nanotube.
Collapse
Affiliation(s)
- Hannu-Pekka Komsa
- COMP, Department of Applied Physics, Aalto University , P.O. Box 11100, 00076 Aalto, Finland
| | - Ryosuke Senga
- Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), AIST Central 5, Tsukuba, Ibaraki 305-8565, Japan
| | - Kazutomo Suenaga
- Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), AIST Central 5, Tsukuba, Ibaraki 305-8565, Japan
| | - Arkady V Krasheninnikov
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research , 01328 Dresden, Germany
- Department of Applied Physics, Aalto University , P.O. Box 11100, 00076 Aalto, Finland
- National University of Science and Technology MISiS , 4 Leninskiy Prospekt, Moscow 119049, Russian Federation
| |
Collapse
|
11
|
Zhao JZ, Fan W, Verstraete MJ, Zanolli Z, Fan J, Yang XB, Xu H, Tong SY. Quasi-One-Dimensional Metal-Insulator Transitions in Compound Semiconductor Surfaces. PHYSICAL REVIEW LETTERS 2016; 117:116101. [PMID: 27661702 DOI: 10.1103/physrevlett.117.116101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Indexed: 06/06/2023]
Abstract
Existing examples of Peierls-type 1D systems on surfaces involve depositing metallic overlayers on semiconducting substrates, in particular, at step edges. Here we propose a new class of Peierls system on the (101[over ¯]0) surface of metal-anion wurtzite semiconductors. When the anions are bonded to hydrogen or lithium atoms, we obtain rows of threefold coordinated metal atoms that act as one-atom-wide metallic structures. First-principles calculations show that the surface is metallic, and below a certain critical temperature the surface will condense to a semiconducting state. The idea of surface scaffolding is introduced in which the rows are constrained to move along simple up-down and/or sideways displacements, mirroring the paradigm envisioned in Peierls's description. We predict that this type of insulating state should be visible in the partially hydrogenated (101[over ¯]0) surface of many wurtzite compounds.
Collapse
Affiliation(s)
- J Z Zhao
- Department of Physics, South University of Science and Technology of China, 518055 Shenzhen, People's Republic of China
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023 Dalian, People's Republic of China
| | - W Fan
- Computational Condensed Matter Physics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
| | - M J Verstraete
- Département de Physique and European Theoretical Spectroscopy Facility, Universite de Liège, B-4000 Sart Tilman, Liège, Belgium
| | - Z Zanolli
- Peter Grünberg Institute (PGI-1) and Institute for Advanced Simulation (IAS-1), Forschungszebtrum Jülich, D-52425 Jülich, Germany
- Institute for Theoretical Solid State Physics and European Theoretical Spectroscopy Facility (ETSF), RWTH Aachen University, D-52056 Aachen, Germany
- Department of Physics, South China University of Technology, Guangzhou 510640, People's Republic of China
| | - J Fan
- Department of Physics, South University of Science and Technology of China, 518055 Shenzhen, People's Republic of China
| | - X B Yang
- School of Science and Engineering, The Chinese University of Hong Kong (Shenzhen), 518172 Shenzhen, People's Republic of China
| | - H Xu
- Department of Physics, South University of Science and Technology of China, 518055 Shenzhen, People's Republic of China
| | - S Y Tong
- Department of Physics, South University of Science and Technology of China, 518055 Shenzhen, People's Republic of China
- School of Science and Engineering, The Chinese University of Hong Kong (Shenzhen), 518172 Shenzhen, People's Republic of China
| |
Collapse
|
12
|
Jałochowski M, Kwapiński T, Łukasik P, Nita P, Kopciuszyński M. Correlation between morphology, electron band structure, and resistivity of Pb atomic chains on the Si(5 5 3)-Au surface. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:284003. [PMID: 27228462 DOI: 10.1088/0953-8984/28/28/284003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Structural and electron transport properties of multiple Pb atomic chains fabricated on the Si(5 5 3)-Au surface are investigated using scanning tunneling spectroscopy, reflection high electron energy diffraction, angular resolved photoemission electron spectroscopy and in situ electrical resistance. The study shows that Pb atomic chains growth modulates the electron band structure of pristine Si(5 5 3)-Au surface and hence changes its sheet resistivity. Strong correlation between chains morphology, electron band structure and electron transport properties is found. To explain experimental findings a theoretical tight-binding model of multiple atomic chains interacting on effective substrate is proposed.
Collapse
Affiliation(s)
- M Jałochowski
- Institute of Physics, M. Curie-Skłodowska University, Pl. M. Curie-Skłodowskiej 1, PL-20-031 Lublin, Poland
| | | | | | | | | |
Collapse
|
13
|
Aulbach J, Erwin SC, Claessen R, Schäfer J. Spin Chains and Electron Transfer at Stepped Silicon Surfaces. NANO LETTERS 2016; 16:2698-2704. [PMID: 26974012 DOI: 10.1021/acs.nanolett.6b00354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
High-index surfaces of silicon with adsorbed gold can reconstruct to form highly ordered linear step arrays. These steps take the form of a narrow strip of graphitic silicon. In some cases--specifically, for Si(553)-Au and Si(557)-Au--a large fraction of the silicon atoms at the exposed edge of this strip are known to be spin-polarized and charge-ordered along the edge. The periodicity of this charge ordering is always commensurate with the structural periodicity along the step edge and hence leads to highly ordered arrays of local magnetic moments that can be regarded as "spin chains." Here, we demonstrate theoretically as well as experimentally that the closely related Si(775)-Au surface has--despite its very similar overall structure--zero spin polarization at its step edge. Using a combination of density-functional theory and scanning tunneling microscopy, we propose an electron-counting model that accounts for these differences. The model also predicts that unintentional defects and intentional dopants can create local spin moments at Si(hhk)-Au step edges. We analyze in detail one of these predictions and verify it experimentally. This finding opens the door to using techniques of surface chemistry and atom manipulation to create and control silicon spin chains.
Collapse
Affiliation(s)
- J Aulbach
- Physikalisches Institut and Röntgen Center for Complex Material Systems (RCCM), Universität Würzburg , D-97074 Würzburg, Germany
| | - S C Erwin
- Center for Computational Materials Science, Naval Research Laboratory , Washington, DC 20375, United States
| | - R Claessen
- Physikalisches Institut and Röntgen Center for Complex Material Systems (RCCM), Universität Würzburg , D-97074 Würzburg, Germany
| | - J Schäfer
- Physikalisches Institut and Röntgen Center for Complex Material Systems (RCCM), Universität Würzburg , D-97074 Würzburg, Germany
| |
Collapse
|
14
|
Song I, Goh JS, Lee SH, Jung SW, Shin JS, Yamane H, Kosugi N, Yeom HW. Realization of a Strained Atomic Wire Superlattice. ACS NANO 2015; 9:10621-10627. [PMID: 26446292 DOI: 10.1021/acsnano.5b04377] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A superlattice of strained Au-Si atomic wires is successfully fabricated on a Si surface. Au atoms are known to incorporate into the stepped Si(111) surface to form a Au-Si atomic wire array with both one-dimensional (1D) metallic and antiferromagnetic atomic chains. At a reduced density of Au, we find a regular array of Au-Si wires in alternation with pristine Si nanoterraces. Pristine Si nanoterraces impose a strain on the neighboring Au-Si wires, which modifies both the band structure of metallic chains and the magnetic property of spin chains. This is an ultimate 1D version of a strained-layer superlattice of semiconductors, defining a direction toward the fine engineering of self-assembled atomic-scale wires.
Collapse
Affiliation(s)
- Inkyung Song
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS) , 77 Cheongam-Ro, Pohang 790-784, Korea
| | - Jung Suk Goh
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS) , 77 Cheongam-Ro, Pohang 790-784, Korea
| | - Sung-Hoon Lee
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS) , 77 Cheongam-Ro, Pohang 790-784, Korea
| | - Sung Won Jung
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS) , 77 Cheongam-Ro, Pohang 790-784, Korea
| | - Jin Sung Shin
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS) , 77 Cheongam-Ro, Pohang 790-784, Korea
| | - Hiroyuki Yamane
- Department of Photo-Molecular Science, Institute for Molecular Science , Okazaki 444-8585, Japan
| | - Nobuhiro Kosugi
- Department of Photo-Molecular Science, Institute for Molecular Science , Okazaki 444-8585, Japan
| | - Han Woong Yeom
- Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS) , 77 Cheongam-Ro, Pohang 790-784, Korea
- Department of Physics, Pohang University of Science and Technology (POSTECH) , Pohang 790-784, Republic of Korea
| |
Collapse
|
15
|
Song I, Oh DH, Shin HC, Ahn SJ, Moon Y, Woo SH, Choi HJ, Park CY, Ahn JR. Direct momentum-resolved observation of one-dimensional confinement of externally doped electrons within a single subnanometer-scale wire. NANO LETTERS 2015; 15:281-288. [PMID: 25539134 DOI: 10.1021/nl503558g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Cutting-edge research in the band engineering of nanowires at the ultimate fine scale is related to the minimum scale of nanowire-based devices. The fundamental issue at the subnanometer scale is whether angle-resolved photoemission spectroscopy (ARPES) can be used to directly measure the momentum-resolved electronic structure of a single wire because of the difficulty associated with assembling single wire into an ordered array for such measurements. Here, we demonstrated that the one-dimensional (1D) confinement of electrons, which are transferred from external dopants, within a single subnanometer-scale wire (subnanowire) could be directly measured using ARPES. Convincing evidence of 1D electron confinement was obtained using two different gold subnanowires with characteristic single metallic bands that were alternately and spontaneously ordered on a stepped silicon template, Si(553). Noble metal atoms were adsorbed at room temperature onto the gold subnanowires while the overall structure of the wires was maintained. Only one type of gold subnanowire could be controlled using external noble metal dopants without transforming the metallic band of the other type of gold subnanowires. This result was confirmed by scanning tunnelling microscopy experiments and first-principles calculations. The selective control clearly showed that externally doped electrons could be confined within a single gold subnanowire. This experimental evidence was used to further investigate the effects of the disorder induced by external dopants on a single subnanowire using ARPES.
Collapse
Affiliation(s)
- Inkyung Song
- Department of Physics, ‡Department of Energy Science, and §SAINT, Sungkyunkwan University , Suwon 440-746, Republic of Korea
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Kröger P, Sologub S, Tegenkamp C, Pfnür H. Scattering of charge carriers by Cr impurities in magnetotransport on a Bi(1 1 1) ultra-thin film. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:225002. [PMID: 24810521 DOI: 10.1088/0953-8984/26/22/225002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this investigation we tested the role of Cr impurities on the strongly spin-polarized surface states of ultra-thin epitaxially grown Bi(1 1 1) films by measuring surface magnetoconductance and the Hall effect in conjunction with low-energy electron diffraction at a low temperature (10 K). Compared with Fe and Co, investigated recently, Cr atoms turned out to have scattering cross-sections that are about a factor of three higher than the former atoms. Nevertheless, only a small electron donation (0.03 e/atom) was found for Cr. It also exhibits strong spin-orbit scattering, as judged from quantitative analysis of weak localization effects. As a result, all spin-dependent selection rules are gradually relaxed with increasing Cr concentration, so that the initially observed weak anti-localization shifts towards weak localization. The non-monotonic decrease of conductance as a function of Cr concentration, even at 10 K, indicates high diffusivity and activated adsorption into its final optimal adsorption site.
Collapse
Affiliation(s)
- P Kröger
- Institut für Festkörperphysik, Abteilung Atomare und Molekulare Strukturen, Leibniz Universität Hannover, Appelstr. 2, D-30167 Hannover, Germany
| | | | | | | |
Collapse
|
17
|
Vanpoucke DEP. Modeling 1D structures on semiconductor surfaces: synergy of theory and experiment. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:133001. [PMID: 24599293 DOI: 10.1088/0953-8984/26/13/133001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Atomic scale nanowires attract enormous interest in a wide range of fields. On the one hand, due to their quasi-one-dimensional nature, they can act as an experimental testbed for exotic physics: Peierls instability, charge density waves, and Luttinger liquid behavior. On the other hand, due to their small size, they are of interest not only for future device applications in the micro-electronics industry, but also for applications regarding molecular electronics. This versatile nature makes them interesting systems to produce and study, but their size and growth conditions push both experimental production and theoretical modeling to their limits. In this review, modeling of atomic scale nanowires on semiconductor surfaces is discussed, focusing on the interplay between theory and experiment. The current state of modeling efforts on Pt- and Au-induced nanowires on Ge(001) is presented, indicating their similarities and differences. Recently discovered nanowire systems (Ir, Co, Sr) on the Ge(001) surface are also touched upon. The importance of scanning tunneling microscopy as a tool for direct comparison of theoretical and experimental data is shown, as is the power of density functional theory as an atomistic simulation approach. It becomes clear that complementary strengths of theoretical and experimental investigations are required for successful modeling of the atomistic nanowires, due to their complexity.
Collapse
Affiliation(s)
- Danny E P Vanpoucke
- Center for Molecular Modeling, Ghent University, Technologiepark 903, 9053 Zwijnaarde, Belgium
| |
Collapse
|
18
|
Kwapiński T. Electronic properties of a quantum wire interacting with a surface: the role of periodically placed impurities. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:415304. [PMID: 24060853 DOI: 10.1088/0953-8984/25/41/415304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The transmittance and density of states (DOS) of a quantum wire which is tunnel coupled to the underlying substrate are investigated theoretically using the retarded Green's function method. The wire is composed of periodically placed impurities with Coulomb interactions and is modeled by a tight-binding Hamiltonian within the mean-field approximation. For a given periodicity of impurities along the wire we observe energy gaps in the structure of DOS. These gaps disappear for a wire coupled with the substrate electrode with localized electrons which leads to a metal-insulator transition in the system. Our numerical studies reveal that the transmittance through the system strongly depends on whether or not the substrate electrons are localized.
Collapse
Affiliation(s)
- T Kwapiński
- Institute of Physics, M Curie-Skłodowska University, 20-031 Lublin, Poland
| |
Collapse
|
19
|
Polei S, Snijders PC, Erwin SC, Himpsel FJ, Meiwes-Broer KH, Barke I. Structural transition in atomic chains driven by transient doping. PHYSICAL REVIEW LETTERS 2013; 111:156801. [PMID: 24160617 DOI: 10.1103/physrevlett.111.156801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Indexed: 06/02/2023]
Abstract
A reversible structural transition is observed on Si(553)-Au by scanning tunneling microscopy, triggered by electrons injected from the tip into the surface. The periodicity of atomic chains near the step edges changes from the 1×3 ground state to a 1×2 excited state with increasing tunneling current. The threshold current for this transition is reduced at lower temperatures. In conjunction with first-principles density-functional calculations it is shown that the 1×2 phase is created by temporary doping of the atom chains. Random telegraph fluctuations between two levels of the tunneling current provide direct access to the dynamics of the phase transition, revealing lifetimes in the millisecond range.
Collapse
Affiliation(s)
- S Polei
- Department of Physics, University of Rostock, D-18051 Rostock, Germany
| | | | | | | | | | | |
Collapse
|
20
|
Aulbach J, Schäfer J, Erwin SC, Meyer S, Loho C, Settelein J, Claessen R. Evidence for long-range spin order instead of a Peierls transition in si(553)-Au chains. PHYSICAL REVIEW LETTERS 2013; 111:137203. [PMID: 24116812 DOI: 10.1103/physrevlett.111.137203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Indexed: 06/02/2023]
Abstract
Stabilization of the Si(553) surface by Au adsorption results in two different atomically defined chain types, one of Au atoms and one of Si. At low temperature these chains develop two- and threefold periodicity, respectively, previously attributed to Peierls instabilities. Here we report evidence from scanning tunneling microscopy that rules out this interpretation. The ×3 superstructure of the Si chains vanishes for low tunneling bias, i.e., close the Fermi level. In addition, the Au chains remain metallic despite their period doubling. Both observations are inconsistent with a Peierls mechanism. On the contrary, our results are in excellent, detailed agreement with the Si(553)-Au ground state predicted by density-functional theory, where the ×2 periodicity of the Au chain is an inherent structural feature and every third Si atom is spin polarized.
Collapse
Affiliation(s)
- J Aulbach
- Physikalisches Institut and Röntgen Center for Complex Materials Systems (RCCM), Universität Würzburg, D-97074 Würzburg, Germany
| | | | | | | | | | | | | |
Collapse
|
21
|
Shin HC, Seo JT, Yeom HW, Ahn JR. Temperature dependence of the electronic structure of two-dimensional Na gas on the Si(111)-7 × 7 surface. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:305004. [PMID: 23836777 DOI: 10.1088/0953-8984/25/30/305004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The temperature dependence of the irreversible phase transition from a two-dimensional gas to an ordered zero-dimensional solid on the Si(111)-7 × 7 surface was studied using photoemission spectroscopy. With increasing Na coverage, the two-dimensional Na gas, which is a state of highly mobile Na atoms, undergoes a phase transition into ordered zero-dimensional magic nanoclusters at room temperature. The critical Na coverage of the phase transition was found to increase with reduced temperature. This was used to develop a gas-solid phase diagram of Na atoms on the Si(111)-7 × 7 surface as a function of Na coverage and sample temperature based on the electronic structure. The temperature dependence of the phase transition can be ascribed to the suppression of the thermal energy that is required to overcome the energetic barrier between the two-dimensional gas and the zero-dimensional solid at low temperature, where three different hopping mechanisms are related to the phase transition.
Collapse
Affiliation(s)
- H-C Shin
- Department of Physics, Sungkyunkwan University, Suwon 440-746, Republic of Korea
| | | | | | | |
Collapse
|
22
|
Blumenstein C, Meyer S, Mietke S, Schäfer J, Bostwick A, Rotenberg E, Matzdorf R, Claessen R. Au-induced quantum chains on Ge(001)-symmetries, long-range order and the conduction path. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:014015. [PMID: 23220774 DOI: 10.1088/0953-8984/25/1/014015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Atomic nanowires on the Au/Ge(001) surface are investigated for their structural and electronic properties using scanning tunneling microscopy (STM) and angle-resolved photoemission spectroscopy (ARPES). STM reveals two distinct symmetries: a c(8 × 2) describing the basic repeating distances, while the fine structure on top of the wires causes an additional superstructure of p(4 × 1). Both symmetries are long-range ordered as judged from low-energy electron diffraction. The Fermi surface is composed of almost perfectly straight sheets. Thus, the electronic states are one-dimensionally confined. Spatial dI/dV maps, where both topography and density of states (DOS) are probed simultaneously, reveal that the DOS at low energies, i.e. the conduction path, is oriented along the chain direction. This is fully consistent with the recently reported Tomonaga-Luttinger liquid phase of Au/Ge(001), with the density of states being suppressed by a power-law towards the Fermi energy.
Collapse
Affiliation(s)
- C Blumenstein
- Physikalisches Institut, Universität Würzburg, Germany
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Dähne M, Wanke M. Metallic rare-earth silicide nanowires on silicon surfaces. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:014012. [PMID: 23221358 DOI: 10.1088/0953-8984/25/1/014012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The formation, atomic structure, and electronic properties of self-assembled rare-earth silicide nanowires on silicon surfaces were studied by scanning tunneling microscopy and angle-resolved photoelectron spectroscopy. Metallic dysprosium and erbium silicide nanowires were observed on both the Si(001) and Si(557) surfaces. It was found that they consist of hexagonal rare-earth disilicides for both surface orientations. On Si(001), the nanowires are characterized by a one-dimensional band structure, while the electronic dispersion is two-dimensional for the nanowires formed on Si(557). This behavior is explained by the different orientations of the hexagonal c axis of the silicide leading to different conditions for the carrier confinement. By considering this carrier confinement it is demonstrated how the one-dimensional band structure of the nanowires on Si(001) can be derived from the two-dimensional one of the silicide monolayer on Si(111).
Collapse
Affiliation(s)
- Mario Dähne
- Institut für Festkörperphysik, Technische Universität Berlin, Germany.
| | | |
Collapse
|
24
|
Nita P, Jałochowski M, Krawiec M, Stȩpniak A. One-dimensional diffusion of Pb atoms on the Si(553)-Au surface. PHYSICAL REVIEW LETTERS 2011; 107:026101. [PMID: 21797623 DOI: 10.1103/physrevlett.107.026101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Indexed: 05/31/2023]
Abstract
One-dimensional diffusion along long atomic chains of the Si(553)-Au surface is studied with scanning tunneling microscopy. Ab initio calculations reveal aligned preferential adsorption sites between Si step edge atomic chain and double Au atomic chain on each terrace. At 220 K the Pb atoms hop between shallow potential basins forming a potential groove and move parallel to the atomic chains. By combining the results of measurements with the model calculations of the Pb atoms static energy on the Si(553)-Au surface the attempt frequency ν₀ is determined.
Collapse
Affiliation(s)
- P Nita
- Institute of Physics, Maria Curie-Skłodowska University, Place M. Curie-Skłodowskiej 1, PL-20031 Lublin, Poland
| | | | | | | |
Collapse
|
25
|
Intrinsic magnetism at silicon surfaces. Nat Commun 2010; 1:58. [DOI: 10.1038/ncomms1056] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Accepted: 07/28/2010] [Indexed: 11/08/2022] Open
|
26
|
Hasegawa S. Quasi-one-dimensional metals on semiconductor surfaces with defects. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:084026. [PMID: 21389402 DOI: 10.1088/0953-8984/22/8/084026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Several examples are known in which massive arrays of metal atomic chains are formed on semiconductor surfaces that show quasi-one-dimensional metallic electronic structures. In this review, Au chains on Si(557) and Si(553) surfaces, and In chains on Si(111) surfaces, are introduced and discussed with regard to the physical properties determined by experimental data from scanning tunneling microscopy (STM), angle-resolved photoemission spectroscopy (ARPES) and electrical conductivity measurements. They show quasi-one-dimensional Fermi surfaces and parabolic band dispersion along the chains. All of them are known from STM and ARPES to exhibit metal-insulator transitions by cooling and charge-density-wave formation due to Peierls instability of the metallic chains. The electrical conductivity, however, reveals the metal-insulator transition only on the less-defective surfaces (Si(553)-Au and Si(111)-In), but not on a more-defective surface (Si(557)-Au). The latter shows an insulating character over the whole temperature range. Compared with the electronic structure (Fermi surfaces and band dispersions), the transport property is more sensitive to the defects. With an increase in defect density, the conductivity only along the metal atomic chains was significantly reduced, showing that atomic-scale point defects decisively interrupt the electrical transport along the atomic chains and hide the intrinsic property of transport in quasi-one-dimensional systems.
Collapse
Affiliation(s)
- Shuji Hasegawa
- Department of Physics, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japanhttp://www-surface.phys.s.u-tokyo.ac.jp
| |
Collapse
|
27
|
Hong IH, Yen SC, Lin FS. Two-dimensional self-organization of an ordered Au silicide nanowire network on a Si(110)-16 x 2 surface. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2009; 5:1855-1861. [PMID: 19544319 DOI: 10.1002/smll.200900286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A well-ordered two-dimensional (2D) network consisting of two crossed Au silicide nanowire (NW) arrays is self-organized on a Si(110)-16 x 2 surface by the direct-current heating of approximately 1.5 monolayers of Au on the surface at 1100 K. Such a highly regular crossbar nanomesh exhibits both a perfect long-range spatial order and a high integration density over a mesoscopic area, and these two self-ordering crossed arrays of parallel-aligned NWs have distinctly different sizes and conductivities. NWs are fabricated with widths and pitches as small as approximately 2 and approximately 5 nm, respectively. The difference in the conductivities of two crossed-NW arrays opens up the possibility for their utilization in nanodevices of crossbar architecture. Scanning tunneling microscopy/spectroscopy studies show that the 2D self-organization of this perfect Au silicide nanomesh can be achieved through two different directional electromigrations of Au silicide NWs along different orientations of two nonorthogonal 16 x 2 domains, which are driven by the electrical field of direct-current heating. Prospects for this Au silicide nanomesh are also discussed.
Collapse
Affiliation(s)
- Ie-Hong Hong
- Department of Applied Physics, National Chiayi University, Chiayi 60004, Taiwan.
| | | | | |
Collapse
|
28
|
Saedi A, van Houselt A, van Gastel R, Poelsema B, Zandvliet HJW. Playing pinball with atoms. NANO LETTERS 2009; 9:1733-1736. [PMID: 18781806 DOI: 10.1021/nl8022884] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We demonstrate the feasibility of controlling an atomic scale mechanical device by an external electrical signal. On a germanium substrate, a switching motion of pairs of atoms is induced by electrons that are directly injected into the atoms with a scanning tunneling microscope tip. By precisely controlling the tip current and distance we make two atom pairs behave like the flippers of an atomic-sized pinball machine. This atomic scale mechanical device exhibits six different configurations.
Collapse
Affiliation(s)
- Amirmehdi Saedi
- Physical Aspects of Nanoelectronics and Solid State Physics, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, NL-7500AE Enschede, The Netherlands
| | | | | | | | | |
Collapse
|
29
|
Grioni M, Pons S, Frantzeskakis E. Recent ARPES experiments on quasi-1D bulk materials and artificial structures. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:023201. [PMID: 21813968 DOI: 10.1088/0953-8984/21/2/023201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The spectroscopy of quasi-one-dimensional (1D) systems has been a subject of strong interest since the first experimental observations of unusual line shapes in the early 1990s. Angle-resolved photoemission (ARPES) measurements performed with increasing accuracy have greatly broadened our knowledge of the properties of bulk 1D materials and, more recently, of artificial 1D structures. They have yielded a direct view of 1D bands, of open Fermi surfaces, and of characteristic instabilities. They have also provided unique microscopic evidence for the non-conventional, non-Fermi-liquid, behavior predicted by theory, and for strong and singular interactions. Here we briefly review some of the remarkable experimental results obtained in the last decade.
Collapse
Affiliation(s)
- M Grioni
- Institut de Physique des Nanostructures, École Polytechnique Fédérale de Lausanne-EPFL, CH-1015 Lausanne, Switzerland
| | | | | |
Collapse
|
30
|
Structural Study of the Si(553)-Au Surface. E-JOURNAL OF SURFACE SCIENCE AND NANOTECHNOLOGY 2009. [DOI: 10.1380/ejssnt.2009.533] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
31
|
Schäfer J, Blumenstein C, Meyer S, Wisniewski M, Claessen R. New model system for a one-dimensional electron liquid: self-organized atomic gold chains on Ge(001). PHYSICAL REVIEW LETTERS 2008; 101:236802. [PMID: 19113576 DOI: 10.1103/physrevlett.101.236802] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Indexed: 05/27/2023]
Abstract
Unique electronic properties of self-organized Au atom chains on Ge(001) in novel c(8 x 2) long-range order are revealed by scanning tunneling microscopy. Along the nanowires an exceptionally narrow conduction path exists which is virtually decoupled from the substrate. It is laterally confined to the ultimate limit of single atom dimension, and is strictly separated from its neighbors, as not previously reported. The resulting tunneling conductivity shows a dramatic inhomogeneity of 2 orders of magnitude. The atom chains thus represent an outstandingly close approach to a one-dimensional electron liquid.
Collapse
Affiliation(s)
- J Schäfer
- Physikalisches Institut, Universität Würzburg, 97074 Würzburg, Germany
| | | | | | | | | |
Collapse
|
32
|
Zhou PH, Moras P, Ferrari L, Bihlmayer G, Blügel S, Carbone C. One-dimensional 3d electronic bands of monatomic Cu chains. PHYSICAL REVIEW LETTERS 2008; 101:036807. [PMID: 18764278 DOI: 10.1103/physrevlett.101.036807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2008] [Indexed: 05/26/2023]
Abstract
The electronic structure of an array of monatomic Cu chains grown on the Pt(997) surface has been examined by angle-resolved photoemission. The monatomic wires exhibit properties associated with 3d electron confinement in one dimension. Along the wire direction, the 3d bands states display a dispersive character, with periodicity in reciprocal space defined by the wire array geometry. These observations are compared and analyzed with ab initio calculations based on the full-potential linearized augmented plane-wave method.
Collapse
Affiliation(s)
- P H Zhou
- International Center for Theoretical Physics, Trieste, Italy
| | | | | | | | | | | |
Collapse
|
33
|
Kang PG, Jeong H, Yeom HW. Hopping domain wall induced by paired adatoms on an atomic wire: si(111)-(5 x 2)-Au. PHYSICAL REVIEW LETTERS 2008; 100:146103. [PMID: 18518054 DOI: 10.1103/physrevlett.100.146103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Indexed: 05/26/2023]
Abstract
We observed an inhomogeneous fluctuation along one-dimensional atomic wires self-assembled on a Si(111) surface using scanning tunneling microscopy. The fluctuation exhibits dynamic behavior at room temperature and is observed only in a specific geometric condition; the spacing between two neighboring adatom defects is discommensurate with the wire lattice. Upon cooling, the dynamic fluctuation freezes to show the existence of an atomic-scale dislocation or domain wall induced by such "unfavorably" paired adatoms. The microscopic characteristics of the dynamic fluctuation are explained in terms of a hopping solitonic domain wall, and a local potential for this motion imposed by the adatoms is quantified.
Collapse
Affiliation(s)
- Pil-Gyu Kang
- Institute of Physics and Applied Physics and Center for Atomic Wires and Layers, Yonsei University, Seoul 120-749, Korea
| | | | | |
Collapse
|
34
|
Choi WH, Kang PG, Ryang KD, Yeom HW. Band-structure engineering of gold atomic wires on silicon by controlled doping. PHYSICAL REVIEW LETTERS 2008; 100:126801. [PMID: 18517895 DOI: 10.1103/physrevlett.100.126801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2007] [Indexed: 05/26/2023]
Abstract
We report on the systematic tuning of the electronic band structure of atomic wires by controlling the density of impurity atoms. The atomic wires are self-assembled on Si(111) by substitutional gold adsorbates and extra silicon atoms are deposited as the impurity dopants. The one-dimensional electronic band of gold atomic wires, measured by angle-resolved photoemission, changes from a fully metallic to semiconducting one with its band gap increasing above 0.3 eV along with an energy shift as a linear function of the Si dopant density. The gap opening mechanism is suggested to be related to the ordering of the impurities.
Collapse
Affiliation(s)
- Won Hoon Choi
- Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749, Korea
| | | | | | | |
Collapse
|
35
|
Battaglia C, Cercellier H, Monney C, Despont L, Garnier MG, Aebi P. Unveiling new systematics in the self-assembly of atomic chains on Si(111). ACTA ACUST UNITED AC 2008. [DOI: 10.1088/1742-6596/100/5/052078] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
36
|
Surface X-ray Diffraction Study of the Metal-Insulator Transition on the Si(553)-Au Surface. E-JOURNAL OF SURFACE SCIENCE AND NANOTECHNOLOGY 2008. [DOI: 10.1380/ejssnt.2008.281] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
37
|
Kim KS, Morikawa H, Choi WH, Yeom HW. Strong lateral electron coupling of pb nanowires on stepped si(111): angle-resolved photoemission studies. PHYSICAL REVIEW LETTERS 2007; 99:196804. [PMID: 18233104 DOI: 10.1103/physrevlett.99.196804] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Indexed: 05/25/2023]
Abstract
We employ angle-resolved photoemission to characterize the electronic band structure of the Pb "nanowire" array self-assembled on a stepped Si(111) surface. Despite the highly oriented nanowires observed in scanning tunneling microscopy images, we find essentially two-dimensional Fermi contours modulated one dimensionally perpendicular to the wires. This strong two-dimensional and quasi-one-dimensional nature of the band structure explains the stability and anisotropy of the metallic phase down to 4 K as reported recently. A simple tight-binding model with each Si nanoterrace covered by a densely packed Pb overlayer successfully reproduces this modulated band structure and quantifies the electron coupling within the "nanostripes" and the step-edge potential.
Collapse
Affiliation(s)
- Keun Su Kim
- Institute of Physics and Applied Physics and Center for Atomic Wires and Layers, Yonsei University, Seoul, Korea
| | | | | | | |
Collapse
|
38
|
Schwingenschlögl U, Schuster C. Electronic structure of the c(4×2) reconstructed Ge(001) surface. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2007.10.060] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
39
|
Zandvliet HJW, van Gastel R. Bistability in the shape transition of strained islands. PHYSICAL REVIEW LETTERS 2007; 99:136103. [PMID: 17930613 DOI: 10.1103/physrevlett.99.136103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2007] [Indexed: 05/25/2023]
Abstract
The equilibrium shape of a monatomic strained island on a substrate depends on the step free energies and the difference in surface stress between the island and the substrate. For small island sizes the step free energies dominate, resulting in compact islands. Beyond a critical island size, however, the strain energy becomes dominant and the island maximizes its perimeter, resulting in elongated islands. Here we show that for strained islands with force monopoles pointing in opposing directions at neighboring steps, a regime exists near the critical island size where both compact and elongated shapes can coexist.
Collapse
Affiliation(s)
- H J W Zandvliet
- Physical Aspects of Nanoelectronics, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | | |
Collapse
|
40
|
Barke I, Zheng F, Rügheimer TK, Himpsel FJ. Experimental evidence for spin-split bands in a one-dimensional chain structure. PHYSICAL REVIEW LETTERS 2006; 97:226405. [PMID: 17155823 DOI: 10.1103/physrevlett.97.226405] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2006] [Indexed: 05/12/2023]
Abstract
Gold atom chains on vicinal Si(111) surfaces exhibit an unusual doublet of half-filled bands, whose origin has remained uncertain. The splitting is identified by angle-resolved photoemission as a spin splitting induced by the spin-orbit interaction (Rashba effect), in agreement with a theoretical prediction by Sánchez-Portal, Riikonen, and Martin. This interaction leads to a characteristic pattern of avoided band crossings at a superlattice zone boundary. Two out of four crossings are avoided, with a minigap E_{G}=85 meV and a k offset of 0.05 A;{-1}.
Collapse
Affiliation(s)
- I Barke
- Department of Physics, University of Wisconsin Madison, 1150 University Ave., Madison, Wisconsin 53706, USA
| | | | | | | |
Collapse
|
41
|
Yeom HW. Comment on "Soft phonon, dynamical fluctuations, and a reversible phase transition: indium chains on silicon". PHYSICAL REVIEW LETTERS 2006; 97:189701; discussion 189702. [PMID: 17155590 DOI: 10.1103/physrevlett.97.189701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2006] [Indexed: 05/12/2023]
Affiliation(s)
- H W Yeom
- Center for Atomic Wires and Layers and Institute of Physics and Applied Physics Yonsei University Seoul, 120-749, Korea
| |
Collapse
|
42
|
|
43
|
Snijders PC, Rogge S, Weitering HH. Competing periodicities in fractionally filled one-dimensional bands. PHYSICAL REVIEW LETTERS 2006; 96:076801. [PMID: 16606121 DOI: 10.1103/physrevlett.96.076801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2005] [Indexed: 05/08/2023]
Abstract
We present a variable temperature scanning tunneling microscopy and spectroscopy study of the Si(553)-Au atomic chain reconstruction. This quasi-one-dimensional system undergoes at least two charge density wave (CDW) transitions, which can be attributed to electronic instabilities in the fractionally filled 1D bands of the high-symmetry phase. Upon cooling, Si(553)-Au first undergoes a single-band Peierls distortion, resulting in period doubling along the chains. This Peierls state is ultimately overcome by a competing x3 CDW, which is accompanied by a x2 periodicity in between the chains. These locked-in periodicities indicate small charge transfer between the nearly 1/2-filled and 1/4-filled bands. The presence and the mobility of atomic-scale dislocations in the x3 CDW state indicates the possibility of manipulating phase solitons carrying a (spin, charge) of (1/2, +/- e/3) or (0, +/-2e/3).
Collapse
Affiliation(s)
- P C Snijders
- Kavli Institute of NanoScience, Delft University of Technology, 2628 CJ Delft, The Netherlands
| | | | | |
Collapse
|
44
|
Yeom HW, Kim YK, Lee EY, Ryang KD, Kang PG. Robust one-dimensional metallic band structure of silicide nanowires. PHYSICAL REVIEW LETTERS 2005; 95:205504. [PMID: 16384071 DOI: 10.1103/physrevlett.95.205504] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2005] [Indexed: 05/05/2023]
Abstract
Angle-resolved photoemission (ARP) is employed to investigate the electronic structure of an extremely anisotropic form of nanocrystals--GdSi(2-x) nanowires on Si(100). Using a stepped Si(100) surface, a well-ordered and uniformly oriented array of nanowires is formed along the step edges as confirmed by diffraction and microscopy. The ARP measurement discloses two distinct electronic bands near the Fermi level, which disperse one dimensionally along the nanowires. These bands are metallic with the electron filling of 1/4 and 2/5, respectively, and with the effective mass close to that of a free electron along the wires. The metallicity is robust down to 20 K, in contrast to metallic surface atomic chain systems, paving a way to further studies on one-dimensional physics of metallic nanowires.
Collapse
Affiliation(s)
- H W Yeom
- Center for Atomic Wires and Layers and Institute of Physics and Applied Physics, Yonsei University, Seoul, 120-749, Korea.
| | | | | | | | | |
Collapse
|