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Detection of a Chirality-Induced Spin Selective Quantum Capacitance in α-Helical Peptides.

ABSTRACT: Advanced Kelvin probe force microscopy simultaneously detects the quantum capacitance and surface potential of an α-helical peptide monolayer. These indicators shift when either the magnetic polarization or the enantiomer is toggled. A model based on a triangular quantum well in thermal and chemical equilibrium and electron-electron interactions allows for calculating the electrical potential profile from the measured data. The combination of the model and the measurements shows that no global charge transport is required to produce effects attributed to the chirality-induced spin selectivity effect. These experimental findings support the theoretical model of Fransson et al. Nano Letters 2021, 21 (7), 3026-3032. Measurements of the quantum capacitance represent a new way to test and refine theoretical models used to explain strong spin polarization due to chirality-induced spin selectivity.

SUBMITTER: Theiler PM

PROVIDER: S-EPMC10510583 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature

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Detection of a Chirality-Induced Spin Selective Quantum Capacitance in α-Helical Peptides.

Theiler Pius Markus PM Ritz Christian C Hofmann Raphael R Stemmer Andreas A

Nano letters 20230831 17

Advanced Kelvin probe force microscopy simultaneously detects the quantum capacitance and surface potential of an α-helical peptide monolayer. These indicators shift when either the magnetic polarization or the enantiomer is toggled. A model based on a triangular quantum well in thermal and chemical equilibrium and electron-electron interactions allows for calculating the electrical potential profile from the measured data. The combination of the model and the measurements shows that no global c ...[more]

PMID: 37650519

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