1
|
Abhervé A, Mercier N, Kumar A, Das TK, Even J, Katan C, Kepenekian M. Chirality Versus Symmetry: Electron's Spin Selectivity in Nonpolar Chiral Lead-Bromide Perovskites. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2305784. [PMID: 37527791 DOI: 10.1002/adma.202305784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/29/2023] [Indexed: 08/03/2023]
Abstract
In the last decade, chirality-induced spin selectivity (CISS), the spin-selective electron transport through chiral molecules, has been described in a large range of materials, from insulators to superconductors. Because more experimental studies are desired for the theoretical understanding of the CISS effect, chiral metal-halide semiconductors may contribute to the field thanks to their chiroptical and spintronic properties. In this regard, this work uses new chiral organic cations S-HP1A and R-HP1A (HP1A = 2-hydroxy-propyl-1-ammonium) to prepare 2D chiral halide perovskites (HPs) which crystallize in the enantiomorphic space groups P43 21 2 and P41 21 2, respectively. The fourfold symmetry induces antiferroelectricity along the stacking axis which, combined to incomplete Rashba-like splitting in each individual 2D polar layer, results in rare spin textures in the band structure. As revealed by magnetic conductive-probe atomic force microscopy (AFM) measurements, these materials show CISS effect with partial spin polarization (SP; ±40-45%). This incomplete effect is efficient enough to drive a chiro-spintronic device as demonstrated by the fabrication of spin valve devices with magnetoresistance (MR) responses up to 250 K. Therefore, these stable lead-bromide HP materials not only represent interesting candidates for spintronic applications but also reveal the importance of polar symmetry-breaking topology for spin selectivity.
Collapse
Affiliation(s)
- Alexandre Abhervé
- MOLTECH-Anjou, UMR 6200, CNRS, UNIV Angers, 2 bd Lavoisier, ANGERS, Cedex, 49045, France
| | - Nicolas Mercier
- MOLTECH-Anjou, UMR 6200, CNRS, UNIV Angers, 2 bd Lavoisier, ANGERS, Cedex, 49045, France
| | - Anil Kumar
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Tapan Kumar Das
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Jacky Even
- Univ Rennes, INSA Rennes, CNRS, Institut FOTON - UMR 6082, Rennes, F-35000, France
| | - Claudine Katan
- Univ Rennes, ENSCR, CNRS, ISCR - UMR 6226, Rennes, F-35000, France
| | | |
Collapse
|
2
|
Caridad JM, Power SR, Lotz MR, Shylau AA, Thomsen JD, Gammelgaard L, Booth TJ, Jauho AP, Bøggild P. Conductance quantization suppression in the quantum Hall regime. Nat Commun 2018; 9:659. [PMID: 29440635 PMCID: PMC5811439 DOI: 10.1038/s41467-018-03064-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 01/17/2018] [Indexed: 11/14/2022] Open
Abstract
Conductance quantization is the quintessential feature of electronic transport in non-interacting mesoscopic systems. This phenomenon is observed in quasi one-dimensional conductors at zero magnetic field B, and the formation of edge states at finite magnetic fields results in wider conductance plateaus within the quantum Hall regime. Electrostatic interactions can change this picture qualitatively. At finite B, screening mechanisms in narrow, gated ballistic conductors are predicted to give rise to an increase in conductance and a suppression of quantization due to the appearance of additional conduction channels. Despite being a universal effect, this regime has proven experimentally elusive because of difficulties in realizing one-dimensional systems with sufficiently hard-walled, disorder-free confinement. Here, we experimentally demonstrate the suppression of conductance quantization within the quantum Hall regime for graphene nanoconstrictions with low edge roughness. Our findings may have profound impact on fundamental studies of quantum transport in finite-size, two-dimensional crystals with low disorder. Conductance quantization is the hallmark of non-interacting confined systems. The authors show that the quantization in graphene nanoconstrictions with low edge disorder is suppressed in the quantum Hall regime. This is explained by the addition of new conductance channels due to electrostatic screening.
Collapse
Affiliation(s)
- José M Caridad
- Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark.
| | - Stephen R Power
- Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark.,Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, Barcelona, 08193, Spain.,Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), 08193, Spain
| | - Mikkel R Lotz
- Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Artsem A Shylau
- Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Joachim D Thomsen
- Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Lene Gammelgaard
- Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Timothy J Booth
- Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Antti-Pekka Jauho
- Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - Peter Bøggild
- Center for Nanostructured Graphene (CNG), Department of Micro- and Nanotechnology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark.
| |
Collapse
|
3
|
Kendirlik EM, Sirt S, Kalkan SB, Ofek N, Umansky V, Siddiki A. The local nature of incompressibility of quantum Hall effect. Nat Commun 2017; 8:14082. [PMID: 28071652 PMCID: PMC5234089 DOI: 10.1038/ncomms14082] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 11/23/2016] [Indexed: 11/23/2022] Open
Abstract
Since the experimental realization of the integer quantum Hall effect in a two-dimensional electron system, the interrelation between the conductance quantization and the topological properties of the system has been investigated. Assuming that the two-dimensional electron system is described by a Bloch Hamiltonian, system is insulating in the bulk of sample throughout the quantum Hall plateau due to a magnetic field induced energy gap. Meanwhile, the system is conducting at the edges resembling a 2+1 dimensional topological insulator without time-reversal symmetry. Here, by our magneto-transport measurements performed on GaAs/AlGaAs high purity Hall bars with two inner contacts we show that incompressible strips formed at the edges result in Hall quantization, even if the bulk is compressible. Consequently, the relationship between the quantum Hall effect and topological bulk insulator breaks for specific field intervals within the plateaus. The measurement of conducting bulk, strongly challenges all existing single-particle theories. Edge current quantization in the integer quantum Hall effect is understood to arise due to noninteracting electrons circulating an incompressible insulating bulk. Here, the authors evidence compressible metal-like bulk behaviour in GaAs/AlGaAs Hall bars consistent with electronic interactions.
Collapse
Affiliation(s)
- E M Kendirlik
- Faculty of Science, Department of Physics, Istanbul University, Vezneciler, Istanbul 34134, Turkey
| | - S Sirt
- Department of Physics, Science and Letters Faculty, Mimar Sinan Fine Arts University, Sisli, Istanbul 34380, Turkey
| | - S B Kalkan
- Faculty of Science, Department of Physics, Istanbul University, Vezneciler, Istanbul 34134, Turkey
| | - N Ofek
- Department of Applied Physics, Yale University, 217 Prospect Street New Haven, Connecticut 06511-8499, USA
| | - V Umansky
- Braun Center for Submicron Research, Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - A Siddiki
- Faculty of Science, Department of Physics, Istanbul University, Vezneciler, Istanbul 34134, Turkey.,Department of Physics, Science and Letters Faculty, Mimar Sinan Fine Arts University, Sisli, Istanbul 34380, Turkey
| |
Collapse
|