1
|
Fransson J, Turin L. Current Induced Spin-Polarization in Chiral Molecules. J Phys Chem Lett 2024; 15:6370-6374. [PMID: 38857512 PMCID: PMC11194818 DOI: 10.1021/acs.jpclett.4c01362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Revised: 06/02/2024] [Accepted: 06/04/2024] [Indexed: 06/12/2024]
Abstract
The inverse spin-galvanic effect or current-induced spin-polarization is mainly associated with interfaces between different layers in semiconducting heterostructures, surfaces of metals, and bulk semiconducting materials. Here, we theoretically predict that the inverse spin-galvanic effect should also be present in chiral molecules, as a result of the chiral induced spin selectivity effect. As proof-of-principle, we calculate the nonequilibrium properties of a model system that previously has been successfully used to explain a multitude of aspects related to the chiral induced spin selectivity effect. Here we show that current driven spin-polarization in a chiral molecule gives rise to a magnetic moment that is sensitive to external magnet field. The chiral molecule then behaves like a soft ferromagnet. This, in turn, suggests that magnetic permeability measurement in otherwise nonmagnetic systems may be used noninvasively to detect the presence of spin-polarized currents.
Collapse
Affiliation(s)
- J. Fransson
- Department
of Physics and Astronomy, Box 516, 751 20, Uppsala University, Uppsala 751 21, Sweden
| | - L. Turin
- Clore
Laboratory, University of Buckingham, Buckingham MK18 1EG, U.K.
| |
Collapse
|
2
|
Okamoto J, Wang RP, Chu YY, Shiu HW, Singh A, Huang HY, Mou CY, Teh S, Jeng HT, Du K, Xu X, Cheong SW, Du CH, Chen CT, Fujimori A, Huang DJ. Giant X-Ray Circular Dichroism in a Time-Reversal Invariant Antiferromagnet. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2309172. [PMID: 38391035 DOI: 10.1002/adma.202309172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 02/09/2024] [Indexed: 02/24/2024]
Abstract
X-ray circular dichroism, arising from the contrast in X-ray absorption between opposite photon helicities, serves as a spectroscopic tool to measure the magnetization of ferromagnetic materials and identify the handedness of chiral crystals. Antiferromagnets with crystallographic chirality typically lack X-ray magnetic circular dichroism because of time-reversal symmetry, yet exhibit weak X-ray natural circular dichroism. Here, the observation of giant natural circular dichroism in the Ni L3-edge X-ray absorption of Ni3TeO6 is reported, a polar and chiral antiferromagnet with effective time-reversal symmetry. To unravel this intriguing phenomenon, a phenomenological model is proposed that classifies the movement of photons in a chiral crystal within the same symmetry class as that of a magnetic field. The coupling of X-ray polarization with the induced magnetization yields giant X-ray natural circular dichroism, revealing typical ferromagnetic behaviors allowed by the symmetry in an antiferromagnet, i.e., the altermagnetism of Ni3TeO6. The findings provide evidence for the interplay between magnetism and crystal chirality in natural optical activity. Additionally, the first example of a new class of magnetic materials exhibiting circular dichroism is established with time-reversal symmetry.
Collapse
Affiliation(s)
- Jun Okamoto
- National Synchrotron Radiation Research Center, Hsinchu, 30076, Taiwan
| | - Ru-Pan Wang
- Department of Physics, University of Hamburg, Luruper Chaussee 149, G610, 22761, Hamburg, Germany
| | - Yen-Yi Chu
- National Synchrotron Radiation Research Center, Hsinchu, 30076, Taiwan
| | - Hung-Wei Shiu
- National Synchrotron Radiation Research Center, Hsinchu, 30076, Taiwan
| | - Amol Singh
- National Synchrotron Radiation Research Center, Hsinchu, 30076, Taiwan
| | - Hsiao-Yu Huang
- National Synchrotron Radiation Research Center, Hsinchu, 30076, Taiwan
| | - Chung-Yu Mou
- Center for Quantum Science and Technology and Department of Physics, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Sukhito Teh
- Department of Physics, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Horng-Tay Jeng
- Department of Physics, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Kai Du
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, 08854, USA
| | - Xianghan Xu
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, 08854, USA
| | - Sang-Wook Cheong
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, 08854, USA
| | - Chao-Hung Du
- Department of Physics, Tamkang University, Tamsui, 251, Taiwan
| | - Chien-Te Chen
- National Synchrotron Radiation Research Center, Hsinchu, 30076, Taiwan
| | - Atsushi Fujimori
- National Synchrotron Radiation Research Center, Hsinchu, 30076, Taiwan
- Center for Quantum Science and Technology and Department of Physics, National Tsing Hua University, Hsinchu, 30013, Taiwan
- Department of Physics, University of Tokyo, Bunkyo-Ku, Tokyo, 113-0033, Japan
| | - Di-Jing Huang
- National Synchrotron Radiation Research Center, Hsinchu, 30076, Taiwan
- Department of Physics, National Tsing Hua University, Hsinchu, 30013, Taiwan
- Department of Electrophysics, National Yang Ming Chiao Tung University, Hsinchu, 30093, Taiwan
| |
Collapse
|
3
|
Bloom BP, Paltiel Y, Naaman R, Waldeck DH. Chiral Induced Spin Selectivity. Chem Rev 2024; 124:1950-1991. [PMID: 38364021 PMCID: PMC10906005 DOI: 10.1021/acs.chemrev.3c00661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 01/16/2024] [Accepted: 01/23/2024] [Indexed: 02/18/2024]
Abstract
Since the initial landmark study on the chiral induced spin selectivity (CISS) effect in 1999, considerable experimental and theoretical efforts have been made to understand the physical underpinnings and mechanistic features of this interesting phenomenon. As first formulated, the CISS effect refers to the innate ability of chiral materials to act as spin filters for electron transport; however, more recent experiments demonstrate that displacement currents arising from charge polarization of chiral molecules lead to spin polarization without the need for net charge flow. With its identification of a fundamental connection between chiral symmetry and electron spin in molecules and materials, CISS promises profound and ubiquitous implications for existing technologies and new approaches to answering age old questions, such as the homochiral nature of life. This review begins with a discussion of the different methods for measuring CISS and then provides a comprehensive overview of molecules and materials known to exhibit CISS-based phenomena before proceeding to identify structure-property relations and to delineate the leading theoretical models for the CISS effect. Next, it identifies some implications of CISS in physics, chemistry, and biology. The discussion ends with a critical assessment of the CISS field and some comments on its future outlook.
Collapse
Affiliation(s)
- Brian P. Bloom
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Yossi Paltiel
- Applied
Physics Department and Center for Nano-Science and Nano-Technology, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Ron Naaman
- Department
of Chemical and Biological Physics, Weizmann
Institute, Rehovot 76100, Israel
| | - David H. Waldeck
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| |
Collapse
|
4
|
Tirion SH, van Wees BJ. Mechanism for Electrostatically Generated Magnetoresistance in Chiral Systems without Spin-Dependent Transport. ACS NANO 2024; 18:6028-6037. [PMID: 38353652 PMCID: PMC10906072 DOI: 10.1021/acsnano.3c12925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 01/29/2024] [Accepted: 01/31/2024] [Indexed: 02/28/2024]
Abstract
Significant attention has been drawn to electronic transport in chiral materials coupled to ferromagnets in the chirality-induced spin selectivity (CISS) effect. A large magnetoresistance (MR) is usually observed, which is widely interpreted to originate from spin (dependent) transport. However, there are severe discrepancies between the experimental results and the theoretical interpretations, most notably the apparent failure of the Onsager reciprocity relations in the linear response regime. We provide an alternative mechanism for the two terminal MR in chiral systems coupled to a ferromagnet. For this, we point out that it was observed experimentally that the electrostatic contact potential of chiral materials on a ferromagnet depends on the magnetization direction and chirality. The mechanism that we provide causes the transport barrier to be modified by the magnetization direction, already in equilibrium, in the absence of a bias current. This strongly alters the charge transport through and over the barrier, not requiring spin transport. This provides a mechanism that allows the linear response resistance to be sensitive to the magnetization direction and also explains the failure of the Onsager reciprocity relations. We propose experimental configurations to confirm our alternative mechanism for MR.
Collapse
Affiliation(s)
- Sytze H. Tirion
- Zernike Institute for Advanced
Materials, University of Groningen, NL-9747AG Groningen, The Netherlands
| | - Bart J. van Wees
- Zernike Institute for Advanced
Materials, University of Groningen, NL-9747AG Groningen, The Netherlands
| |
Collapse
|
5
|
Hedegård P. Spin dynamics and chirality induced spin selectivity. J Chem Phys 2023; 159:104104. [PMID: 37694743 DOI: 10.1063/5.0160233] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 08/14/2023] [Indexed: 09/12/2023] Open
Abstract
By now, it is well known that chiral molecules can affect the spin of electrons passing through. In addition, the magnetization of, e.g., nanomagnets covered by chiral molecules can be affected by the presence of molecules. We are studying the mechanisms that explain various observations involving combinations of magnets and chiral molecules. We find that there exists a molecule induced contribution to the magnetic anisotropy of the magnets. Out of equilibrium, when electrons are actually being transported through a nano-magnet covered with chiral molecules, a molecule induced torque acting on the magnetization is emerging. It is of the spin-transfer-torque kind, already discussed in other parts of spintronics. This current induced torque can help explain the observed breaking of the Onsager reciprocity principle in experiments involving magnets and chiral molecules.
Collapse
Affiliation(s)
- Per Hedegård
- Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, Copenhagen 2100, Denmark
| |
Collapse
|
6
|
Volpi M, Jouclas R, Liu J, Liu G, Catalano L, McIntosh N, Bardini M, Gatsios C, Modesti F, Turetta N, Beljonne D, Cornil J, Kennedy AR, Koch N, Erk P, Samorì P, Schweicher G, Geerts YH. Enantiopure Dinaphtho[2,3-b:2,3-f]thieno[3,2-b]thiophenes: Reaching High Magnetoresistance Effect in OFETs. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2301914. [PMID: 37424043 PMCID: PMC10502826 DOI: 10.1002/advs.202301914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/29/2023] [Indexed: 07/11/2023]
Abstract
Chiral molecules are known to behave as spin filters due to the chiral induced spin selectivity (CISS) effect. Chirality can be implemented in molecular semiconductors in order to study the role of the CISS effect in charge transport and to find new materials for spintronic applications. In this study, the design and synthesis of a new class of enantiopure chiral organic semiconductors based on the well-known dinaphtho[2,3-b:2,3-f]thieno[3,2-b]thiophene (DNTT) core functionalized with chiral alkyl side chains is presented. When introduced in an organic field-effect transistor (OFET) with magnetic contacts, the two enantiomers, (R)-DNTT and (S)-DNTT, show an opposite behavior with respect to the relative direction of the magnetization of the contacts, oriented by an external magnetic field. Each enantiomer displays an unexpectedly high magnetoresistance over one preferred orientation of the spin current injected from the magnetic contacts. The result is the first reported OFET in which the current can be switched on and off upon inversion of the direction of the applied external magnetic field. This work contributes to the general understanding of the CISS effect and opens new avenues for the introduction of organic materials in spintronic devices.
Collapse
Affiliation(s)
- Martina Volpi
- Laboratoire de Chimie des PolymèresFaculté des SciencesUniversité Libre de Bruxelles (ULB)Boulevard du Triomphe, CP 206/01Bruxelles1050Belgium
| | - Rémy Jouclas
- Laboratoire de Chimie des PolymèresFaculté des SciencesUniversité Libre de Bruxelles (ULB)Boulevard du Triomphe, CP 206/01Bruxelles1050Belgium
| | - Jie Liu
- Laboratoire de Chimie des PolymèresFaculté des SciencesUniversité Libre de Bruxelles (ULB)Boulevard du Triomphe, CP 206/01Bruxelles1050Belgium
| | - Guangfeng Liu
- Laboratoire de Chimie des PolymèresFaculté des SciencesUniversité Libre de Bruxelles (ULB)Boulevard du Triomphe, CP 206/01Bruxelles1050Belgium
| | - Luca Catalano
- Laboratoire de Chimie des PolymèresFaculté des SciencesUniversité Libre de Bruxelles (ULB)Boulevard du Triomphe, CP 206/01Bruxelles1050Belgium
| | - Nemo McIntosh
- Laboratory for Chemistry of Novel MaterialsCenter for Research in Molecular Electronics and PhotonicsUniversity of MonsPlace du Parc 23MonsB‐7000Belgium
| | - Marco Bardini
- Laboratory for Chemistry of Novel MaterialsCenter for Research in Molecular Electronics and PhotonicsUniversity of MonsPlace du Parc 23MonsB‐7000Belgium
| | - Christos Gatsios
- Helmholtz‐Zentrum Berlin für Materialien und Energie GmbH12489BerlinGermany
- Institut für Physik and IRIS AdlershofHumboldt‐Universitat zu Berlin12489BerlinGermany
| | | | - Nicholas Turetta
- CNRSUniversity of StrasbourgISIS UMR 7006, 8 Alleé Gaspard MongeStrasbourgF‐67000France
| | - David Beljonne
- Laboratory for Chemistry of Novel MaterialsCenter for Research in Molecular Electronics and PhotonicsUniversity of MonsPlace du Parc 23MonsB‐7000Belgium
| | - Jérôme Cornil
- Laboratory for Chemistry of Novel MaterialsCenter for Research in Molecular Electronics and PhotonicsUniversity of MonsPlace du Parc 23MonsB‐7000Belgium
| | - Alan R. Kennedy
- Department of Pure and Applied ChemistryUniversity of StrathclydeCathedral Street 295GlasgowG1 1XLUK
| | - Norbert Koch
- Helmholtz‐Zentrum Berlin für Materialien und Energie GmbH12489BerlinGermany
- Institut für Physik and IRIS AdlershofHumboldt‐Universitat zu Berlin12489BerlinGermany
| | - Peter Erk
- BASF SERGD – J542S67056Ludwigshafen am RheinGermany
| | - Paolo Samorì
- CNRSUniversity of StrasbourgISIS UMR 7006, 8 Alleé Gaspard MongeStrasbourgF‐67000France
| | - Guillaume Schweicher
- Laboratoire de Chimie des PolymèresFaculté des SciencesUniversité Libre de Bruxelles (ULB)Boulevard du Triomphe, CP 206/01Bruxelles1050Belgium
| | - Yves H. Geerts
- Laboratoire de Chimie des PolymèresFaculté des SciencesUniversité Libre de Bruxelles (ULB)Boulevard du Triomphe, CP 206/01Bruxelles1050Belgium
- International Solvay Institutes for Physics and ChemistryUniversité Libre de Bruxelles (ULB)Boulevard du Triomphe, CP 231Bruxelles1050Belgium
| |
Collapse
|
7
|
Kapon Y, Kammerbauer F, Yochelis S, Kläui M, Paltiel Y. Magneto-optical imaging of magnetic-domain pinning induced by chiral molecules. J Chem Phys 2023; 159:064701. [PMID: 37578062 DOI: 10.1063/5.0159351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 07/12/2023] [Indexed: 08/15/2023] Open
Abstract
Chiral molecules have the potential for creating new magnetic devices by locally manipulating the magnetic properties of metallic surfaces. When chiral polypeptides chemisorb onto ferromagnets, they can induce magnetization locally by spin exchange interactions. However, direct imaging of surface magnetization changes induced by chiral molecules was not previously realized. Here, we use magneto-optical Kerr microscopy to image domains in thin films and show that chiral polypeptides strongly pin domains, increasing the coercive field locally. In our study, we also observe a rotation of the easy magnetic axis toward the out-of-plane, depending on the sample's domain size and the adsorption area. These findings show the potential of chiral molecules to control and manipulate magnetization and open new avenues for future research on the relationship between chirality and magnetization.
Collapse
Affiliation(s)
- Yael Kapon
- Institute of Applied Physics, Faculty of Sciences, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Fabian Kammerbauer
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 7, 55128 Mainz, Germany
| | - Shira Yochelis
- Institute of Applied Physics, Faculty of Sciences, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Mathias Kläui
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 7, 55128 Mainz, Germany
| | - Yossi Paltiel
- Institute of Applied Physics, Faculty of Sciences, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| |
Collapse
|
8
|
Xu Y, Mi W. Chiral-induced spin selectivity in biomolecules, hybrid organic-inorganic perovskites and inorganic materials: a comprehensive review on recent progress. MATERIALS HORIZONS 2023; 10:1924-1955. [PMID: 36989068 DOI: 10.1039/d3mh00024a] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The two spin states of electrons are degenerate in nonmagnetic materials. The chiral-induced spin selectivity (CISS) effect provides a new strategy for manipulating electron's spin and a deeper understanding of spin selective processes in organisms. Here, we summarize the important discoveries and recent experiments performed during the development of the CISS effect, analyze the spin polarized transport in various types of materials and discuss the mechanisms, theoretical calculations, experimental techniques and biological significance of the CISS effect. The first part of this review concisely presents a general overview of the discoveries and importance of the CISS effect, laws and underlying mechanisms of which are discussed in the next section, where several classical experimental methods for detecting the CISS effect are also introduced. Based on the organic and inorganic properties of materials, the CISS effect of organic biomolecules, hybrid organic-inorganic perovskites and inorganic materials are reviewed in the third, fourth and fifth sections, especially the chiral transfer mechanism of hybrid materials and the relationship between the CISS effect and life science. In addition, conclusions and prospective future of the CISS effect are outlined at the end, where the development and applications of the CISS effect in spintronics are directly described, which is helpful for designing promising chiral spintronic devices and understanding the natural status of chirality from a new perspective.
Collapse
Affiliation(s)
- Yingdan Xu
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China.
| | - Wenbo Mi
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China.
| |
Collapse
|
9
|
Yang C, Li Y, Zhou S, Guo Y, Jia C, Liu Z, Houk KN, Dubi Y, Guo X. Real-time monitoring of reaction stereochemistry through single-molecule observations of chirality-induced spin selectivity. Nat Chem 2023:10.1038/s41557-023-01212-2. [PMID: 37188972 DOI: 10.1038/s41557-023-01212-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 04/20/2023] [Indexed: 05/17/2023]
Abstract
Stereochemistry has an essential role in organic synthesis, biological catalysis and physical processes. In situ chirality identification and asymmetric synthesis are non-trivial tasks, especially for single-molecule systems. However, going beyond the chiral characterization of a large number of molecules (which inevitably leads to ensemble averaging) is crucial for elucidating the different properties induced by the chiral nature of the molecules. Here we report direct monitoring of chirality variations during a Michael addition followed by proton transfer and keto-enol tautomerism in a single molecule. Taking advantage of the chirality-induced spin selectivity effect, continuous current measurements through a single-molecule junction revealed in situ chirality variations during the reaction. Chirality identification at a high sensitivity level provides a promising tool for the study of symmetry-breaking reactions and sheds light on the origin of the chirality-induced spin selectivity effect itself.
Collapse
Affiliation(s)
- Chen Yang
- Beijing National Laboratory for Molecular Sciences, National Biomedical Imaging Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, People's Republic of China
| | - Yanwei Li
- Environment Research Institute, Shandong University, Qingdao, People's Republic of China
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA
| | - Shuyao Zhou
- Beijing National Laboratory for Molecular Sciences, National Biomedical Imaging Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, People's Republic of China
| | - Yilin Guo
- Beijing National Laboratory for Molecular Sciences, National Biomedical Imaging Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, People's Republic of China
| | - Chuancheng Jia
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, College of Electronic Information and Optical Engineering, Nankai University, Tianjin, People's Republic of China
| | - Zhirong Liu
- Beijing National Laboratory for Molecular Sciences, National Biomedical Imaging Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, People's Republic of China
| | - Kendall N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA.
| | - Yonatan Dubi
- Department of Chemistry, Ben-Gurion University of the Negev, Be'er-Sheva, Israel.
| | - Xuefeng Guo
- Beijing National Laboratory for Molecular Sciences, National Biomedical Imaging Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, People's Republic of China.
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, College of Electronic Information and Optical Engineering, Nankai University, Tianjin, People's Republic of China.
| |
Collapse
|
10
|
Fransson J. Vibrationally Induced Magnetism in Supramolecular Aggregates. J Phys Chem Lett 2023; 14:2558-2564. [PMID: 36877808 PMCID: PMC10026173 DOI: 10.1021/acs.jpclett.3c00157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
Magnetic phenomena in chemistry and condensed matter physics are considered to be associated with low temperatures. That a magnetic state or order is stable below a critical temperature as well as becoming stronger the lower the temperature is a nearly unquestioned paradigm. It is, therefore, surprising that recent experimental observations made on supramolecular aggregates suggest that, for instance, the magnetic coercivity may increase with an increasing temperature and the chiral-induced spin selectivity effect may be enhanced. Here, a mechanism for vibrationally stabilized magnetism is proposed, and a theoretical model is introduced with which the qualitative aspects of the recent experimental findings can be explained. It is argued that anharmonic vibrations, which become increasingly occupied with an increasing temperature, enable nuclear vibrations to both stabilize and sustain magnetic states. The theoretical proposal, hence, pertains to structures without inversion and/or reflection symmetries, for instance, chiral molecules and crystals.
Collapse
|
11
|
Labella J, Bhowmick DK, Kumar A, Naaman R, Torres T. Easily processable spin filters: exploring the chiral induced spin selectivity of bowl-shaped chiral subphthalocyanines. Chem Sci 2023; 14:4273-4277. [PMID: 37123186 PMCID: PMC10132120 DOI: 10.1039/d3sc01069d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Accepted: 03/15/2023] [Indexed: 04/05/2023] Open
Abstract
Herein a new class of spin filters based on subphthalocyanines is reported. We measure the CISS effect by means of magnetic conductive probe atomic force microscopy (mc-AFM). Remarkably, the resulting devices show spin polarizations (SPs) as high as ca. 50%.
Collapse
Affiliation(s)
- Jorge Labella
- Department of Organic Chemistry, Universidad Autónoma de Madrid, Campus de Cantoblanco, C/Francisco Tomás y Valiente 7, 28049 Madrid, Spain
| | - Deb Kumar Bhowmick
- Department of Chemical and Biological Physics, Weizmann Institute of Science, 7610001, Israel
| | - Anil Kumar
- Department of Chemical and Biological Physics, Weizmann Institute of Science, 7610001, Israel
| | - Ron Naaman
- Department of Chemical and Biological Physics, Weizmann Institute of Science, 7610001, Israel
| | - Tomás Torres
- Department of Organic Chemistry, Universidad Autónoma de Madrid, Campus de Cantoblanco, C/Francisco Tomás y Valiente 7, 28049 Madrid, Spain
- Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, 28049 Madrid, Spain
- IMDEA-Nanociencia, Campus de Cantoblanco, 28049 Madrid, Spain
| |
Collapse
|