A correlated view of chiral-induced spin selectivity

Prof. Jonas Fransson (University of Uppsala)

Thursday May 4, 10 am

ICMCB amphitheatre – Conference de Quantum Matter

Lien vers les infos : QMBx seminar Jonas Fransson 2023 – Quantum Matter Bordeaux (cnrs.fr)

Chiral-induced spin selectivity is an intriguing phenomenon that, to our knowledge, rests on a foundation of structural chirality, spin-orbit interactions, and strongly non-equilibrium conditions. The effect is a measure of the response to changes in the magnetic environment coupled to the active region, and the phenomenology refers back to the experimental observations of substantial changes in the charge current amplitude through chiral molecules upon changes in the external magnetic conditions. Chiral-induced spin selectivity has been shown to not be limited to multistranded helical structures, such as double-stranded DNA molecules and bacteriorhodopsin, but has also been observed in, for example, various types of peptides and polyalanines and, recently, also in helicene.

In order to depart from the generic single electron, or, non-interacting models that have, quite unsuccessfully, been used in attempts to describe the chiral-induced spin selectivity effect, it is proposes to include many-body effects, arising from, e.g., electron-electron or electron-vibron interactions. In cooperation with spin-orbit interactions, the many-body interactions generate exchange splitting between the spin channels which is viable for the chiral-induced spin selectivity phenomenon. By constructing models comprising either electron-electron or electron-vibron interactions, it can be demonstrated that the chiral-induced spin selectivity effect increases by several orders of magnitude compared to the results from any non-interacting description. The phenomenology of the chiral-induced spin selectivity effect indicates that charge transfer within the chiral molecule is accompanied by the emergence of intra-molecular spin-polarization.

  1. Fransson, Chirality induced spin-selectivity: The role of electron correlation: J Phys Chem Lett, 10, 7126 (2019).
  2. Fransson, Vibrational origin of exchange splitting and chiral-induced spin selectivity: Phys Rev B, 102, 235416 (2020).
  3. Fransson, Charge Redistribution and Spin Polarization Driven by Correlation Induced Electron Exchange in Chiral Molecules: Nano Lett, 21, 3026 (2021).
  4. Fransson, Charge and Spin Dynamics and Enantioselectivity in Chiral Molecules: J Phys Chem Lett, 13, 808 (2022).

Contact: Elizabeth Hillard <elizabeth.hillard@icmcb.cnrs.fr>