1
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Wang X, Hu Y, Kim SY, Cho K, Wallace RM. Mechanism of Fermi Level Pinning for Metal Contacts on Molybdenum Dichalcogenide. ACS APPLIED MATERIALS & INTERFACES 2024. [PMID: 38422472 DOI: 10.1021/acsami.3c18332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
The high contact resistance of transition metal dichalcogenide (TMD)-based devices is receiving considerable attention due to its limitation on electronic performance. The mechanism of Fermi level (EF) pinning, which causes the high contact resistance, is not thoroughly understood to date. In this study, the metal (Ni and Ag)/Mo-TMD surfaces and interfaces are characterized by X-ray photoelectron spectroscopy, atomic force microscopy, scanning tunneling microscopy and spectroscopy, and density functional theory systematically. Ni and Ag form covalent and van der Waals (vdW) interfaces on Mo-TMDs, respectively. Imperfections are detected on Mo-TMDs, which lead to electronic and spatial variations. Gap states appear after the adsorption of single and two metal atoms on Mo-TMDs. The combination of the interface reaction type (covalent or vdW), the imperfection variability of the TMD materials, and the gap states induced by contact metals with different weights are concluded to be the origins of EF pinning.
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Affiliation(s)
- Xinglu Wang
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States of America
| | - Yaoqiao Hu
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States of America
| | - Seong Yeoul Kim
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States of America
| | - Kyeongjae Cho
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States of America
| | - Robert M Wallace
- Department of Materials Science and Engineering, The University of Texas at Dallas, Richardson, Texas 75080, United States of America
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2
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Hötger A, Männer W, Amit T, Hernangómez-Pérez D, Taniguchi T, Watanabe K, Wurstbauer U, Finley JJ, Refaely-Abramson S, Kastl C, Holleitner AW. Photovoltage and Photocurrent Absorption Spectra of Sulfur Vacancies Locally Patterned in Monolayer MoS 2. NANO LETTERS 2023; 23:11655-11661. [PMID: 38054904 DOI: 10.1021/acs.nanolett.3c03517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
We report on the optical absorption characteristics of selectively positioned sulfur vacancies in monolayer MoS2, as observed by photovoltage and photocurrent experiments in an atomistic vertical tunneling circuit at cryogenic and room temperature. Charge carriers are resonantly photoexcited within the defect states before they tunnel through an hBN tunneling barrier to a graphene-based drain contact. Both photovoltage and photocurrent characteristics confirm the optical absorption spectrum as derived from ab initio GW and Bethe-Salpeter equation approximations. Our results reveal the potential of single-vacancy tunneling devices as atomic-scale photodiodes.
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Affiliation(s)
- Alexander Hötger
- Walter Schottky Institute and Physics Department, TU Munich, Garching 85748, Germany
| | - Wolfgang Männer
- Walter Schottky Institute and Physics Department, TU Munich, Garching 85748, Germany
| | - Tomer Amit
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Daniel Hernangómez-Pérez
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Takashi Taniguchi
- Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Kenji Watanabe
- Research Center for Electronic and Optical Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Ursula Wurstbauer
- Institute of Physics, Westfälische Wilhelms-Universität Münster, Münster 48149, Germany
| | - Jonathan J Finley
- Walter Schottky Institute and Physics Department, TU Munich, Garching 85748, Germany
| | - Sivan Refaely-Abramson
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Christoph Kastl
- Walter Schottky Institute and Physics Department, TU Munich, Garching 85748, Germany
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3
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Gupta S, Wu W, Huang S, Yakobson BI. Single-Photon Emission from Two-Dimensional Materials, to a Brighter Future. J Phys Chem Lett 2023; 14:3274-3284. [PMID: 36977324 DOI: 10.1021/acs.jpclett.2c03674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Single photons, often called flying qubits, have enormous promise to realize scalable quantum technologies ranging from an unhackable communication network to quantum computers. However, finding an ideal single-photon emitter (SPE) is a great challenge. Recently, two-dimensional (2D) materials have shown great potential as hosts for SPEs that are bright and operate under ambient conditions. This Perspective enumerates the metrics required for an SPE source and highlights that 2D materials, because of reduced dimensionality, exhibit interesting physical effects and satisfy several metrics, making them excellent candidates to host SPEs. The performance of SPE candidates discovered in 2D materials, hexagonal boron nitride and transition metal dichalcogenides, will be assessed based on the metrics, and the remaining challenges will be highlighted. Lastly, strategies to mitigate such challenges by developing design rules to deterministically create SPE sources will be presented.
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Affiliation(s)
- Sunny Gupta
- Department of Materials Science and Nanoengineering, Rice University, Houston, Texas 77005, United States
| | - Wenjing Wu
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, USA
| | - Shengxi Huang
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, USA
| | - Boris I Yakobson
- Department of Materials Science and Nanoengineering, Rice University, Houston, Texas 77005, United States
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
- Smalley-Curl Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005, United States
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4
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Wang W, Jones LO, Chen JS, Schatz GC, Ma X. Utilizing Ultraviolet Photons to Generate Single-Photon Emitters in Semiconductor Monolayers. ACS NANO 2022; 16:21240-21247. [PMID: 36516862 DOI: 10.1021/acsnano.2c09209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The understanding and controlled creation of atomic defects in semiconductor transition metal dichalcogenides (TMDs) are highly relevant to their applications in high-performance quantum optics and nanoelectronic devices. Here, we demonstrate a versatile approach in generating single-photon emitters in MoS2 monolayers using widely attainable UV light. We discover that only defects engendered by UV photons in vacuum exhibit single-photon-emitter characteristics, whereas those created in air lack quantum emission attributes. In combination with theoretical calculations, we assign the defects generated in vacuum to unpassivated sulfur vacancies, whose highly localized midgap states give rise to single-photon emission. In contrast, UV irradiation of the MoS2 monolayers in air results in oxygen-passivated sulfur vacancies, whose optical properties are likely governed by their pristine band-to-defect band optical transitions. These findings suggest that widely available light sources such as UV light can be utilized for creating quantum photon sources in TMDs.
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Affiliation(s)
- Wei Wang
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Leighton O Jones
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Jia-Shiang Chen
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
- Center for Molecular Quantum Transduction, Northwestern-Argonne Institute of Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - George C Schatz
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- Center for Molecular Quantum Transduction, Northwestern-Argonne Institute of Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Xuedan Ma
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
- Consortium for Advanced Science and Engineering, University of Chicago, Chicago, Illinois 60637, United States
- Center for Molecular Quantum Transduction, Northwestern-Argonne Institute of Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
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5
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Grünleitner T, Henning A, Bissolo M, Zengerle M, Gregoratti L, Amati M, Zeller P, Eichhorn J, Stier AV, Holleitner AW, Finley JJ, Sharp ID. Real-Time Investigation of Sulfur Vacancy Generation and Passivation in Monolayer Molybdenum Disulfide via in situ X-ray Photoelectron Spectromicroscopy. ACS NANO 2022; 16:20364-20375. [PMID: 36516326 DOI: 10.1021/acsnano.2c06317] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Understanding the chemical and electronic properties of point defects in two-dimensional materials, as well as their generation and passivation, is essential for the development of functional systems, spanning from next-generation optoelectronic devices to advanced catalysis. Here, we use synchrotron-based X-ray photoelectron spectroscopy (XPS) with submicron spatial resolution to create sulfur vacancies (SVs) in monolayer MoS2 and monitor their chemical and electronic properties in situ during the defect creation process. X-ray irradiation leads to the emergence of a distinct Mo 3d spectral feature associated with undercoordinated Mo atoms. Real-time analysis of the evolution of this feature, along with the decrease of S content, reveals predominant monosulfur vacancy generation at low doses and preferential disulfur vacancy generation at high doses. Formation of these defects leads to a shift of the Fermi level toward the valence band (VB) edge, introduction of electronic states within the VB, and formation of lateral pn junctions. These findings are consistent with theoretical predictions that SVs serve as deep acceptors and are not responsible for the ubiquitous n-type conductivity of MoS2. In addition, we find that these defects are metastable upon short-term exposure to ambient air. By contrast, in situ oxygen exposure during XPS measurements enables passivation of SVs, resulting in partial elimination of undercoordinated Mo sites and reduction of SV-related states near the VB edge. Correlative Raman spectroscopy and photoluminescence measurements confirm our findings of localized SV generation and passivation, thereby demonstrating the connection between chemical, structural, and optoelectronic properties of SVs in MoS2.
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Affiliation(s)
- Theresa Grünleitner
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4, 85748 Garching, Germany
| | - Alex Henning
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4, 85748 Garching, Germany
| | - Michele Bissolo
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4, 85748 Garching, Germany
| | - Marisa Zengerle
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4, 85748 Garching, Germany
| | - Luca Gregoratti
- Elettra - Sincrotrone Trieste SCpA, AREA Science Park, Strada Statale 14 km 163.5, 34149, Trieste, Italy
| | - Matteo Amati
- Elettra - Sincrotrone Trieste SCpA, AREA Science Park, Strada Statale 14 km 163.5, 34149, Trieste, Italy
| | - Patrick Zeller
- Elettra - Sincrotrone Trieste SCpA, AREA Science Park, Strada Statale 14 km 163.5, 34149, Trieste, Italy
| | - Johanna Eichhorn
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4, 85748 Garching, Germany
| | - Andreas V Stier
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4, 85748 Garching, Germany
| | - Alexander W Holleitner
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4, 85748 Garching, Germany
| | - Jonathan J Finley
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4, 85748 Garching, Germany
| | - Ian D Sharp
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4, 85748 Garching, Germany
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6
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Aharonovich I, Tetienne JP, Toth M. Quantum Emitters in Hexagonal Boron Nitride. NANO LETTERS 2022; 22:9227-9235. [PMID: 36413674 DOI: 10.1021/acs.nanolett.2c03743] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Hexagonal boron nitride (hBN) has emerged as a fascinating platform to explore quantum emitters and their applications. Beyond being a wide-bandgap material, it is also a van der Waals crystal, enabling direct exfoliation of atomically thin layers─a combination which offers unique advantages over bulk, 3D crystals. In this Mini Review we discuss the unique properties of hBN quantum emitters and highlight progress toward their future implementation in practical devices. We focus on engineering and integration of the emitters with scalable photonic resonators. We also highlight recently discovered spin defects in hBN and discuss their potential utility for quantum sensing. All in all, hBN has become a front runner in explorations of solid-state quantum science with promising future prospects.
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Affiliation(s)
- Igor Aharonovich
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
- ARC Centre of Excellence for Transformative Meta-Optical Systems, Faculty of Science, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
| | | | - Milos Toth
- School of Mathematical and Physical Sciences, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
- ARC Centre of Excellence for Transformative Meta-Optical Systems, Faculty of Science, University of Technology Sydney, Ultimo, New South Wales 2007, Australia
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7
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Sigger F, Amersdorffer I, Hötger A, Nutz M, Kiemle J, Taniguchi T, Watanabe K, Förg M, Noe J, Finley JJ, Högele A, Holleitner AW, Hümmer T, Hunger D, Kastl C. Ultra-Sensitive Extinction Measurements of Optically Active Defects in Monolayer MoS 2. J Phys Chem Lett 2022; 13:10291-10296. [PMID: 36305703 DOI: 10.1021/acs.jpclett.2c02386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
We utilize cavity-enhanced extinction spectroscopy to directly quantify the optical absorption of defects in MoS2 generated by helium ion bombardment. We achieve hyperspectral imaging of specific defect patterns with a detection limit below 0.01% extinction, corresponding to a detectable defect density below 1 × 1011 cm-2. The corresponding spectra reveal a broad subgap absorption, being consistent with theoretical predictions related to sulfur vacancy-bound excitons in MoS2. Our results highlight cavity-enhanced extinction spectroscopy as efficient means for the detection of optical transitions in nanoscale thin films with weak absorption, applicable to a broad range of materials.
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Affiliation(s)
- Florian Sigger
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4a, 85748Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, 80799Munich, Germany
| | - Ines Amersdorffer
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, 80799Munich, Germany
- Qlibri GmbH, Maistr. 67, 80337Munich, Germany
- Faculty of Physics, Ludwig-Maximilians-Universität München, Schellingstraße 4, 80799Munich, Germany
| | - Alexander Hötger
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4a, 85748Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, 80799Munich, Germany
| | - Manuel Nutz
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, 80799Munich, Germany
- Qlibri GmbH, Maistr. 67, 80337Munich, Germany
- Faculty of Physics, Ludwig-Maximilians-Universität München, Schellingstraße 4, 80799Munich, Germany
| | - Jonas Kiemle
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4a, 85748Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, 80799Munich, Germany
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba 305-0044, Japan
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, Tsukuba305-0044, Japan
| | - Michael Förg
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, 80799Munich, Germany
- Qlibri GmbH, Maistr. 67, 80337Munich, Germany
- Faculty of Physics, Ludwig-Maximilians-Universität München, Schellingstraße 4, 80799Munich, Germany
| | - Jonathan Noe
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, 80799Munich, Germany
- Qlibri GmbH, Maistr. 67, 80337Munich, Germany
- Faculty of Physics, Ludwig-Maximilians-Universität München, Schellingstraße 4, 80799Munich, Germany
| | - Jonathan J Finley
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4a, 85748Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, 80799Munich, Germany
| | - Alexander Högele
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, 80799Munich, Germany
- Faculty of Physics, Ludwig-Maximilians-Universität München, Schellingstraße 4, 80799Munich, Germany
| | - Alexander W Holleitner
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4a, 85748Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, 80799Munich, Germany
| | - Thomas Hümmer
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, 80799Munich, Germany
- Qlibri GmbH, Maistr. 67, 80337Munich, Germany
- Faculty of Physics, Ludwig-Maximilians-Universität München, Schellingstraße 4, 80799Munich, Germany
| | - David Hunger
- Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Str. 1, 76131Karlsruhe, Germany
| | - Christoph Kastl
- Walter Schottky Institute and Physics Department, Technical University of Munich, Am Coulombwall 4a, 85748Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), Schellingstr. 4, 80799Munich, Germany
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8
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Wang G, Wang Y, Li S, Yang Q, Li D, Pantelides ST, Lin J. Engineering the Crack Structure and Fracture Behavior in Monolayer MoS 2 By Selective Creation of Point Defects. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2200700. [PMID: 35644032 PMCID: PMC9353506 DOI: 10.1002/advs.202200700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 03/31/2022] [Indexed: 06/15/2023]
Abstract
Monolayer transition-metal dichalcogenides, e.g., MoS2 , typically have high intrinsic strength and Young's modulus, but low fracture toughness. Under high stress, brittle fracture occurs followed by cleavage along a preferential lattice direction, leading to catastrophic failure. Defects have been reported to modulate the fracture behavior, but pertinent atomic mechanism still remains elusive. Here, sulfur (S) and MoSn point defects are selectively created in monolayer MoS2 using helium- and gallium-ion-beam lithography, both of which reduce the stiffness of the monolayer, but enhance its fracture toughness. By monitoring the atomic structure of the cracks before and after the loading fracture, distinct atomic structures of the cracks and fracture behaviors are found in the two types of defect-containing monolayer MoS2 . Combined with molecular dynamics simulations, the key role of individual S and MoSn point defects is identified in the fracture process and the origin of the enhanced fracture toughness is elucidated. It is a synergistic effect of defect-induced deflection and bifurcation of cracks that enhance the energy release rate, and the formation of widen crack tip when fusing with point defects that prevents the crack propagation. The findings of this study provide insights into defect engineering and flexible device applications of monolayer MoS2 .
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Affiliation(s)
- Gang Wang
- Department of Physics and Shenzhen Key Laboratory of Advanced Quantum Functional Materials and DevicesSouthern University of Science and TechnologyShenzhen518055China
| | - Yun‐Peng Wang
- School of Physics and ElectronicsHunan Key Laboratory for Super‐Micro Structure and Ultrafast ProcessCentral South University932 South Lushan RoadChangsha410083China
| | - Songge Li
- Department of Physics and Shenzhen Key Laboratory of Advanced Quantum Functional Materials and DevicesSouthern University of Science and TechnologyShenzhen518055China
| | - Qishuo Yang
- Department of Physics and Shenzhen Key Laboratory of Advanced Quantum Functional Materials and DevicesSouthern University of Science and TechnologyShenzhen518055China
| | - Daiyue Li
- Department of Physics and Shenzhen Key Laboratory of Advanced Quantum Functional Materials and DevicesSouthern University of Science and TechnologyShenzhen518055China
| | - Sokrates T. Pantelides
- Department of Physics and Astronomy and Department of Electrical and Computer EngineeringVanderbilt UniversityNashvilleTN37235USA
| | - Junhao Lin
- Department of Physics and Shenzhen Key Laboratory of Advanced Quantum Functional Materials and DevicesSouthern University of Science and TechnologyShenzhen518055China
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9
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Ozdemir I, Holleitner AW, Kastl C, Aktürk OÜ. Thickness and defect dependent electronic, optical and thermoelectric features of [Formula: see text]. Sci Rep 2022; 12:12756. [PMID: 35882909 PMCID: PMC9325696 DOI: 10.1038/s41598-022-16899-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 07/18/2022] [Indexed: 11/08/2022] Open
Abstract
Transition metal dichalcogenides (TMDs) receive significant attention due to their outstanding electronic and optical properties. In this study, we investigate the electronic, optical, and thermoelectric properties of single and few layer [Formula: see text] in detail utilizing first-principles methods based on the density functional theory (DFT). Within the scope of both PBE and HSE06 including spin orbit coupling (SOC), the simulations predict the electronic band gap values to decrease as the number of layers increases. Moreover, spin-polarized DFT calculations combined with the semi-classical Boltzmann transport theory are applied to estimate the anisotropic thermoelectric power factor (Seebeck coefficient, S) for [Formula: see text] in both the monolayer and multilayer limit, and S is obtained below the optimal value for practical applications. The optical absorbance of [Formula: see text] monolayer is obtained to be slightly less than the values reported in literature for 2H TMD monolayers of [Formula: see text], [Formula: see text], and [Formula: see text]. Furthermore, we simulate the impact of defects, such as vacancy, antisite and substitution defects, on the electronic, optical and thermoelectric properties of monolayer [Formula: see text]. Particularly, the Te-[Formula: see text] substitution defect in parallel orientation yields negative formation energy, indicating that the relevant defect may form spontaneously under relevant experimental conditions. We reveal that the electronic band structure of [Formula: see text] monolayer is significantly influenced by the presence of the considered defects. According to the calculated band gap values, a lowering of the conduction band minimum gives rise to metallic characteristics to the structure for the single Te(1) vacancy, a diagonal Te line defect, and the Te(1)-[Formula: see text] substitution, while the other investigated defects cause an opening of a small positive band gap at the Fermi level. Consequently, the real ([Formula: see text]) and imaginary ([Formula: see text]) parts of the dielectric constant at low frequencies are very sensitive to the applied defects, whereas we find that the absorbance (A) at optical frequencies is less significantly affected. We also predict that certain point defects can enhance the otherwise moderate value of S in pristine [Formula: see text] to values relevant for thermoelectric applications. The described [Formula: see text] monolayers, as functionalized with the considered defects, offer the possibility to be applied in optical, electronic, and thermoelectric devices.
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Affiliation(s)
- Ilkay Ozdemir
- Physics Department, Adnan Menderes University, 09100 Aydin, Turkey
| | - Alexander W. Holleitner
- Walter Schottky Institut and Physics Department, Technical University of Munich, Am Coulombwall 4a, 85748 Garching, Germany
- Munich Center of Quantum Science and Technology (MCQST), Schellingstr. 4, 80799 Munich, Germany
| | - Christoph Kastl
- Walter Schottky Institut and Physics Department, Technical University of Munich, Am Coulombwall 4a, 85748 Garching, Germany
- Munich Center of Quantum Science and Technology (MCQST), Schellingstr. 4, 80799 Munich, Germany
| | - Olcay Üzengi Aktürk
- Walter Schottky Institut and Physics Department, Technical University of Munich, Am Coulombwall 4a, 85748 Garching, Germany
- Electrical Electronics Engineering Department, Adnan Menderes University, 09100 Aydin, Turkey
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10
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Kirubasankar B, Won YS, Adofo LA, Choi SH, Kim SM, Kim KK. Atomic and structural modifications of two-dimensional transition metal dichalcogenides for various advanced applications. Chem Sci 2022; 13:7707-7738. [PMID: 35865881 PMCID: PMC9258346 DOI: 10.1039/d2sc01398c] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 05/18/2022] [Indexed: 12/14/2022] Open
Abstract
Two-dimensional (2D) transition metal dichalcogenides (TMDs) and their heterostructures have attracted significant interest in both academia and industry because of their unusual physical and chemical properties. They offer numerous applications, such as electronic, optoelectronic, and spintronic devices, in addition to energy storage and conversion. Atomic and structural modifications of van der Waals layered materials are required to achieve unique and versatile properties for advanced applications. This review presents a discussion on the atomic-scale and structural modifications of 2D TMDs and their heterostructures via post-treatment. Atomic-scale modifications such as vacancy generation, substitutional doping, functionalization and repair of 2D TMDs and structural modifications including phase transitions and construction of heterostructures are discussed. Such modifications on the physical and chemical properties of 2D TMDs enable the development of various advanced applications including electronic and optoelectronic devices, sensing, catalysis, nanogenerators, and memory and neuromorphic devices. Finally, the challenges and prospects of various post-treatment techniques and related future advanced applications are addressed.
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Affiliation(s)
- Balakrishnan Kirubasankar
- Department of Energy Science, Sungkyunkwan University Suwon 16419 South Korea .,Department of Chemistry, Sookmyung Women's University Seoul 14072 South Korea
| | - Yo Seob Won
- Department of Energy Science, Sungkyunkwan University Suwon 16419 South Korea .,Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University Suwon 16419 South Korea
| | - Laud Anim Adofo
- Department of Energy Science, Sungkyunkwan University Suwon 16419 South Korea .,Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University Suwon 16419 South Korea
| | - Soo Ho Choi
- Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University Suwon 16419 South Korea
| | - Soo Min Kim
- Department of Chemistry, Sookmyung Women's University Seoul 14072 South Korea
| | - Ki Kang Kim
- Department of Energy Science, Sungkyunkwan University Suwon 16419 South Korea .,Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University Suwon 16419 South Korea
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11
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Garcia-Esparza AT, Park S, Abroshan H, Paredes Mellone OA, Vinson J, Abraham B, Kim TR, Nordlund D, Gallo A, Alonso-Mori R, Zheng X, Sokaras D. Local Structure of Sulfur Vacancies on the Basal Plane of Monolayer MoS 2. ACS NANO 2022; 16:6725-6733. [PMID: 35380038 DOI: 10.1021/acsnano.2c01388] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The nature of the S-vacancy is central to controlling the electronic properties of monolayer MoS2. Understanding the geometric and electronic structures of the S-vacancy on the basal plane of monolayer MoS2 remains elusive. Here, operando S K-edge X-ray absorption spectroscopy shows the formation of clustered S-vacancies on the basal plane of monolayer MoS2 under reaction conditions (H2 atmosphere, 100-600 °C). First-principles calculations predict spectral fingerprints consistent with the experimental results. The Mo K-edge extended X-ray absorption fine structure shows the local structure as coordinatively unsaturated Mo with 4.1 ± 0.4 S atoms as nearest neighbors (above 400 °C in an H2 atmosphere). Conversely, the 6-fold Mo-Mo coordination in the crystal remains unchanged. Electrochemistry confirms similar active sites for hydrogen evolution. The identity of the S-vacancy defect on the basal plane of monolayer MoS2 is herein elucidated for applications in optoelectronics and catalysis.
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Affiliation(s)
- Angel T Garcia-Esparza
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
- Department of Mechanical Engineering, Stanford University, Stanford, California 94305, United States
| | - Sangwook Park
- Department of Mechanical Engineering, Stanford University, Stanford, California 94305, United States
| | - Hadi Abroshan
- SUNCAT Center for Interface Science and Catalysis, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721, United States
| | - Oscar A Paredes Mellone
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
| | - John Vinson
- National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899, United States
| | - Baxter Abraham
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
| | - Taeho R Kim
- Stanford Nano Shared Facilities, Stanford University, Stanford, California 94305, United States
| | - Dennis Nordlund
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
| | - Alessandro Gallo
- SUNCAT Center for Interface Science and Catalysis, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
| | - Roberto Alonso-Mori
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
| | - Xiaolin Zheng
- Department of Mechanical Engineering, Stanford University, Stanford, California 94305, United States
| | - Dimosthenis Sokaras
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
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12
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Ippolito S, Samorì P. Defect Engineering Strategies Toward Controlled Functionalization of Solution‐Processed Transition Metal Dichalcogenides. SMALL SCIENCE 2022. [DOI: 10.1002/smsc.202100122] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Affiliation(s)
- Stefano Ippolito
- CNRS ISIS UMR 7006 University of Strasbourg 8 Allée Gaspard Monge 67000 Strasbourg France
| | - Paolo Samorì
- CNRS ISIS UMR 7006 University of Strasbourg 8 Allée Gaspard Monge 67000 Strasbourg France
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13
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Hole doping effect of MoS 2 via electron capture of He + ion irradiation. Sci Rep 2021; 11:23590. [PMID: 34880289 PMCID: PMC8654839 DOI: 10.1038/s41598-021-02932-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 11/23/2021] [Indexed: 01/02/2023] Open
Abstract
Beyond the general purpose of noble gas ion sputtering, which is to achieve functional defect engineering of two-dimensional (2D) materials, we herein report another positive effect of low-energy (100 eV) He+ ion irradiation: converting n-type MoS2 to p-type by electron capture through the migration of the topmost S atoms. The electron capture ability via He+ ion irradiation is valid for supported bilayer MoS2; however, it is limited at supported monolayer MoS2 because the charges on the underlying substrates transfer into the monolayer under the current condition for He+ ion irradiation. Our technique provides a stable and universal method for converting n-type 2D transition metal dichalcogenides (TMDs) into p-type semiconductors in a controlled fashion using low-energy He+ ion irradiation.
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14
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Choi M, Jun S, Woo KY, Song HG, Yeo HS, Choi S, Park D, Park CH, Cho YH. Nanoscale Focus Pinspot for High-Purity Quantum Emitters via Focused-Ion-Beam-Induced Luminescence Quenching. ACS NANO 2021; 15:11317-11325. [PMID: 34165277 DOI: 10.1021/acsnano.1c00587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Epitaxially grown quantum dots (QDs), especially embedded in photonic structures, play an essential role in various quantum photonic systems as on-demand single-photon sources. However, these QDs often suffer from adjacent unwanted emitters, which contribute to the background noise of the QD emission and fundamentally limit the single-photon purity. In this paper, a nanoscale focus pinspot (NFP) technique using focused-ion-beam-induced luminescence quenching enables us to improve single-photon purity from site-controlled QD as a proof-of-concept experiment. The optical quality of the QD emission is not degraded while the signal-to-noise ratio of the QD is improved. Moreover, the QD after the NFP technique reveals the single-photon nature at further elevated temperatures owing to the reduced background noise. As the NFP technique is nondestructive, it retains the apparent physical structures and photonic functions, thereby indicating its promising potential for applying diverse high-purity quantum emitters, particularly integrated in photonic devices and circuits.
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Affiliation(s)
- Minho Choi
- Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Seongmoon Jun
- Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Kie Young Woo
- Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Hyun Gyu Song
- Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Hwan-Seop Yeo
- Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Sunghan Choi
- Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Doyoun Park
- Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Chung-Hyun Park
- Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Yong-Hoon Cho
- Department of Physics and KI for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
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15
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Mitterreiter E, Schuler B, Micevic A, Hernangómez-Pérez D, Barthelmi K, Cochrane KA, Kiemle J, Sigger F, Klein J, Wong E, Barnard ES, Watanabe K, Taniguchi T, Lorke M, Jahnke F, Finley JJ, Schwartzberg AM, Qiu DY, Refaely-Abramson S, Holleitner AW, Weber-Bargioni A, Kastl C. The role of chalcogen vacancies for atomic defect emission in MoS 2. Nat Commun 2021; 12:3822. [PMID: 34158488 PMCID: PMC8219741 DOI: 10.1038/s41467-021-24102-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 05/28/2021] [Indexed: 11/08/2022] Open
Abstract
For two-dimensional (2D) layered semiconductors, control over atomic defects and understanding of their electronic and optical functionality represent major challenges towards developing a mature semiconductor technology using such materials. Here, we correlate generation, optical spectroscopy, atomic resolution imaging, and ab initio theory of chalcogen vacancies in monolayer MoS2. Chalcogen vacancies are selectively generated by in-vacuo annealing, but also focused ion beam exposure. The defect generation rate, atomic imaging and the optical signatures support this claim. We discriminate the narrow linewidth photoluminescence signatures of vacancies, resulting predominantly from localized defect orbitals, from broad luminescence features in the same spectral range, resulting from adsorbates. Vacancies can be patterned with a precision below 10 nm by ion beams, show single photon emission, and open the possibility for advanced defect engineering of 2D semiconductors at the ultimate scale.
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Grants
- EXC 2089/1-390776260 Deutsche Forschungsgemeinschaft (German Research Foundation)
- RTG 2247 Deutsche Forschungsgemeinschaft (German Research Foundation)
- RTG 2247 Deutsche Forschungsgemeinschaft (German Research Foundation)
- DE-AC02-05CH11231 DOE | Office of Science (SC)
- DE-AC02-05CH11231 DOE | Office of Science (SC)
- DE-AC02-05CH11231 DOE | Office of Science (SC)
- DE-AC02-05CH11231 DOE | Office of Science (SC)
- JPMJCR15F3 MEXT | JST | Core Research for Evolutional Science and Technology (CREST)
- JPMJCR15F3 MEXT | JST | Core Research for Evolutional Science and Technology (CREST)
- JPMXP0112101001 Ministry of Education, Culture, Sports, Science and Technology (MEXT)
- JP20H00354 Ministry of Education, Culture, Sports, Science and Technology (MEXT)
- JPMXP0112101001 Ministry of Education, Culture, Sports, Science and Technology (MEXT)
- Nanosystems Initiative Munich (NIM) Bavaria California Technology Center (BaCaTeC)
- Alexander von Humboldt-Stiftung (Alexander von Humboldt Foundation)
- INCITE, Contract No. DE-AC05-00OR22725
- Bavaria California Technology Center (BaCaTeC) TUM International Graduate School of Science and Engineering (IGSSE)
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Affiliation(s)
- Elmar Mitterreiter
- Walter Schottky Institut and Physics Department, Technical University of Munich, Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), München, Germany
| | - Bruno Schuler
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- nanotech@surfaces Laboratory, Empa - Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
| | - Ana Micevic
- Walter Schottky Institut and Physics Department, Technical University of Munich, Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), München, Germany
| | - Daniel Hernangómez-Pérez
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, Israel
| | - Katja Barthelmi
- Walter Schottky Institut and Physics Department, Technical University of Munich, Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), München, Germany
| | | | - Jonas Kiemle
- Walter Schottky Institut and Physics Department, Technical University of Munich, Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), München, Germany
| | - Florian Sigger
- Walter Schottky Institut and Physics Department, Technical University of Munich, Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), München, Germany
| | - Julian Klein
- Walter Schottky Institut and Physics Department, Technical University of Munich, Garching, Germany
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Edward Wong
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Edward S Barnard
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan
| | - Michael Lorke
- Bremen Center for Computational Materials Science, University of Bremen, Bremen, Germany
- Bremen Institute for Theoretical Physics, University of Bremen, Bremen, Germany
| | - Frank Jahnke
- Bremen Institute for Theoretical Physics, University of Bremen, Bremen, Germany
| | - Johnathan J Finley
- Walter Schottky Institut and Physics Department, Technical University of Munich, Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), München, Germany
| | | | - Diana Y Qiu
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT, USA
| | - Sivan Refaely-Abramson
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, Israel
| | - Alexander W Holleitner
- Walter Schottky Institut and Physics Department, Technical University of Munich, Garching, Germany.
- Munich Center for Quantum Science and Technology (MCQST), München, Germany.
| | | | - Christoph Kastl
- Walter Schottky Institut and Physics Department, Technical University of Munich, Garching, Germany.
- Munich Center for Quantum Science and Technology (MCQST), München, Germany.
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16
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Liang Q, Zhang Q, Zhao X, Liu M, Wee ATS. Defect Engineering of Two-Dimensional Transition-Metal Dichalcogenides: Applications, Challenges, and Opportunities. ACS NANO 2021; 15:2165-2181. [PMID: 33449623 DOI: 10.1021/acsnano.0c09666] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Atomic defects, being the most prevalent zero-dimensional topological defects, are ubiquitous in a wide range of 2D transition-metal dichalcogenides (TMDs). They could be intrinsic, formed during the initial sample growth, or created by postprocessing. Despite the majority of TMDs being largely unaffected after losing chalcogen atoms in the outermost layer, a spectrum of properties, including optical, electrical, and chemical properties, can be significantly modulated, and potentially invoke applicable functionalities utilized in many applications. Hence, controlling chalcogen atomic defects provides an alternative avenue for engineering a wide range of physical and chemical properties of 2D TMDs. In this article, we review recent progress on the role of chalcogen atomic defects in engineering 2D TMDs, with a particular focus on device performance improvements. Various approaches for creating chalcogen atomic defects including nonstoichiometric synthesis and postgrowth treatment, together with their characterization and interpretation are systematically overviewed. The tailoring of optical, electrical, and magnetic properties, along with the device performance enhancement in electronic, optoelectronic, chemical sensing, biomedical, and catalytic activity are discussed in detail. Postformation dynamic evolution and repair of chalcogen atomic defects are also introduced. Finally, we offer our perspective on the challenges and opportunities in this field.
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Affiliation(s)
- Qijie Liang
- Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117551, Singapore
| | - Qian Zhang
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117575, Singapore
| | - Xiaoxu Zhao
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117575, Singapore
| | - Meizhuang Liu
- Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117551, Singapore
| | - Andrew T S Wee
- Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117551, Singapore
- Centre for Advanced 2D Materials, National University of Singapore, 6 Science Drive 2, Singapore 117546, Singapore
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17
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Hötger A, Klein J, Barthelmi K, Sigl L, Sigger F, Männer W, Gyger S, Florian M, Lorke M, Jahnke F, Taniguchi T, Watanabe K, Jöns KD, Wurstbauer U, Kastl C, Müller K, Finley JJ, Holleitner AW. Gate-Switchable Arrays of Quantum Light Emitters in Contacted Monolayer MoS 2 van der Waals Heterodevices. NANO LETTERS 2021; 21:1040-1046. [PMID: 33433221 DOI: 10.1021/acs.nanolett.0c04222] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We demonstrate electrostatic switching of individual, site-selectively generated matrices of single photon emitters (SPEs) in MoS2 van der Waals heterodevices. We contact monolayers of MoS2 in field-effect devices with graphene gates and hexagonal boron nitride as the dielectric and graphite as bottom gates. After the assembly of such gate-tunable heterodevices, we demonstrate how arrays of defects, that serve as quantum emitters, can be site-selectively generated in the monolayer MoS2 by focused helium ion irradiation. The SPEs are sensitive to the charge carrier concentration in the MoS2 and switch on and off similar to the neutral exciton in MoS2 for moderate electron doping. The demonstrated scheme is a first step for producing scalable, gate-addressable, and gate-switchable arrays of quantum light emitters in MoS2 heterostacks.
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Affiliation(s)
- Alexander Hötger
- Walter Schottky Institute and Physics Department, TU Munich, 85748 Garching, Germany
| | - Julian Klein
- Walter Schottky Institute and Physics Department, TU Munich, 85748 Garching, Germany
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Katja Barthelmi
- Walter Schottky Institute and Physics Department, TU Munich, 85748 Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
| | - Lukas Sigl
- Walter Schottky Institute and Physics Department, TU Munich, 85748 Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
| | - Florian Sigger
- Walter Schottky Institute and Physics Department, TU Munich, 85748 Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
| | - Wolfgang Männer
- Walter Schottky Institute and Physics Department, TU Munich, 85748 Garching, Germany
| | - Samuel Gyger
- KTH Royal Institute of Technology, Department of Applied Physics, 10691 Stockholm, Sweden
| | - Matthias Florian
- Institut für Theoretische Physik, Universität Bremen, 28334 Bremen, Germany
| | - Michael Lorke
- Institut für Theoretische Physik, Universität Bremen, 28334 Bremen, Germany
| | - Frank Jahnke
- Institut für Theoretische Physik, Universität Bremen, 28334 Bremen, Germany
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Klaus D Jöns
- KTH Royal Institute of Technology, Department of Applied Physics, 10691 Stockholm, Sweden
| | - Ursula Wurstbauer
- Walter Schottky Institute and Physics Department, TU Munich, 85748 Garching, Germany
- Institute of Physics, Westfälische Wilhelms-Universität Münster, 48149 Münster, Germany
| | - Christoph Kastl
- Walter Schottky Institute and Physics Department, TU Munich, 85748 Garching, Germany
| | - Kai Müller
- Walter Schottky Institute and Physics Department, TU Munich, 85748 Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
| | - Jonathan J Finley
- Walter Schottky Institute and Physics Department, TU Munich, 85748 Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
| | - Alexander W Holleitner
- Walter Schottky Institute and Physics Department, TU Munich, 85748 Garching, Germany
- Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
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18
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Han T, Liu H, Chen S, Chen Y, Wang S, Li Z. Fabrication and Characterization of MoS 2/h-BN and WS 2/h-BN Heterostructures. MICROMACHINES 2020; 11:mi11121114. [PMID: 33339124 PMCID: PMC7765550 DOI: 10.3390/mi11121114] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 12/11/2020] [Accepted: 12/13/2020] [Indexed: 11/16/2022]
Abstract
The general preparation method of large-area, continuous, uniform, and controllable vdW heterostructure materials is provided in this paper. To obtain the preparation of MoS2/h-BN and WS2/h-BN heterostructures, MoS2 and WS2 material are directly grown on the insulating h-BN substrate by atmospheric pressure chemical vapor deposition (APCVD) method, which does not require any intermediate transfer steps. The test characterization of MoS2/h-BN and WS2/h-BN vdW heterostructure materials can be accomplished by optical microscope, AFM, Raman and PL spectroscopy. The Raman peak signal of h-BN material is stronger when the h-BN film is thicker. Compared to the spectrum of MoS2 or WS2 material on SiO2/Si substrate, the Raman and PL spectrum peak positions of MoS2/h-BN heterostructure are blue-shifted, which is due to the presence of local strain, charged impurities and the vdW heterostructure interaction. Additionally, the PL spectrum of WS2 material shows the strong emission peak at 1.96 eV, while the full width half maximum (FWHM) is only 56 meV. The sharp emission peak indicates that WS2/h-BN heterostructure material has the high crystallinity and clean interface. In addition, the peak position and shape of IPM mode characteristic peak are not obvious, which can be explained by the Van der Waals interaction of WS2/h-BN heterostructure. From the above experimental results, the preparation method of heterostructure material is efficient and scalable, which can provide the important support for the subsequent application of TMDs/h-BN heterostructure in nanoelectronics and optoelectronics.
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Affiliation(s)
- Tao Han
- Key Laboratory for Wide-Band Gap Semiconductor Materials and Devices of Education, School of Microelectronics, Xidian University, Xi’an 710071, China; (T.H.); (S.W.); (Z.L.)
| | - Hongxia Liu
- Key Laboratory for Wide-Band Gap Semiconductor Materials and Devices of Education, School of Microelectronics, Xidian University, Xi’an 710071, China; (T.H.); (S.W.); (Z.L.)
- Correspondence: (H.L.); (S.C.); Tel.: +86-130-8756-8718 (H.L.); +86-189-9123-3677 (S.C.)
| | - Shupeng Chen
- Key Laboratory for Wide-Band Gap Semiconductor Materials and Devices of Education, School of Microelectronics, Xidian University, Xi’an 710071, China; (T.H.); (S.W.); (Z.L.)
- Correspondence: (H.L.); (S.C.); Tel.: +86-130-8756-8718 (H.L.); +86-189-9123-3677 (S.C.)
| | - Yanning Chen
- State Grid Key Laboratory of Power Industrial Chip Design and Analysis Technology, Beijing Smart-Chip Microelectronics Technology Co., Ltd., Beijing 100192, China;
| | - Shulong Wang
- Key Laboratory for Wide-Band Gap Semiconductor Materials and Devices of Education, School of Microelectronics, Xidian University, Xi’an 710071, China; (T.H.); (S.W.); (Z.L.)
| | - Zhandong Li
- Key Laboratory for Wide-Band Gap Semiconductor Materials and Devices of Education, School of Microelectronics, Xidian University, Xi’an 710071, China; (T.H.); (S.W.); (Z.L.)
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