Influence of electronic-vibrational coupling on spin-selectivity in chiral molecular junctions

Chirality-induced spin selectivity (CISS) describes the phenomenon that the transport of electrons through a chiral molecule depends on the spin polarization of the electrons. The CISS effect has been measured in a variety of setups, however, a detailed understanding of the underlying mechanisms is still elusive [1]. Theoretical studies have pursued different mechanisms, including many-body effects induced by electron-electron interaction or electronic-vibrational coupling [2]. In this talk, we investigate the role of the coupling of the electrons to the molecular vibrations in transport scenarios where the molecule is coupled to leads in a junction. The study uses the hierarchical quantum master equation approach HEOM [3,4] to describe transport processes and considers different models of electronic-vibrational coupling in chiral molecules [5,6,7]. The results show that the influence of electronic-vibrational coupling depends on the specific model and the physical parameters. The underlying mechanisms are analyzed in some detail.

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[5] J. Fransson, Phys. Rev. B 102, 235416 (2020)

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[7] R. Smorka, S. L. Rudge, and M. Thoss, J. Chem. Phys. 126, 014304 (2025)