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Updated: Jul 9, 2025
08:39
Whole-cell Patch-clamp Recordings for Electrophysiological Determination of Ion Selectivity in Channelrhodopsins
Published on: May 22, 2017
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Spin-Selective Electron Transport Through Single Chiral Molecules.
Mohammad Reza Safari1,2, Frank Matthes1,2, Claus M Schneider1,2,3
1Peter Grünberg Institute, Electronic Properties (PGI-6), Forschungszentrum Jülich, 52425, Jülich, Germany.
Small (Weinheim an Der Bergstrasse, Germany)
|December 5, 2023
Summary
Chirality-induced spin selectivity (CISS) shows spin-polarized electron transport in single helical molecules. This study reveals magnetochiral conductance asymmetries, ruling out common mechanisms for CISS.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Surface Science
Background:
- Chirality and magnetism interplay has long fascinated scientists.
- Chirality-induced spin selectivity (CISS) is a phenomenon where electron transport through chiral molecules results in spin polarization.
- Despite experimental evidence, the precise mechanism of CISS remains unclear.
Purpose of the Study:
- To investigate spin-selective electron transport in single helical aromatic hydrocarbons.
- To explore the magnetochiral conductance asymmetry in chiral molecular systems.
- To elucidate the underlying mechanism of CISS by ruling out alternative explanations.
Main Methods:
- Spin-polarized scanning tunneling microscopy (SP-STM) was employed.
- Single helical aromatic hydrocarbons were deposited on ferromagnetic cobalt surfaces under vacuum.
- Measurements were conducted at 5 K, comparing enantiomers under identical conditions.
Main Results:
- Significant magnetochiral conductance asymmetries (up to 50%) were observed.
- Asymmetries were modulated by changing molecular handedness or reversing magnetization of the tip/substrate.
- The findings exclude electron-phonon coupling and ensemble effects as primary CISS mechanisms.
Conclusions:
- Single helical molecules exhibit pronounced spin-selective transport.
- The study provides direct evidence for magnetochiral effects in chiral molecular systems.
- This work advances the understanding of CISS mechanisms at the single-molecule level.
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