Modelling electron dynamics in chiral systems

Chirality-induced spin selectivity (CISS) encompasses a range of phenomena wherein the spin orientation of electrons within a chiral environment influences their behavior. CISS was initially observed in photoemission experiments conducted by Naaman et al., where he revealed significant asymmetry in scattering probabilities as spin-polarized electrons traversed through a thin layer of chiral molecules[1]. Notably, even at the level of single molecules, a remarkable efficiency in spin filtration was observed[2]. Over the past two decades, significant efforts have been devoted to elucidating and demonstrating the impact of chirality on electron behavior, driven by the immense potential for applications in fields such as quantum technologies, spintronics, and enantioselective chemistry. Inspired by the recent discoveries in the field [3], we investigate the mechanism behind CISS using different models and techniques to take care of both the photophysical properties and the transport properties. We exploite the Hubbard model to understand the interplay between the molecular structure, the value of the Spin-Orbit Coupling (SOC), and electron correlation. We explore the photophysical aspects by examining the time evolution of systems on a conical intersection within the framework of open quantum systems formalism. Additionally, we investigate the transport using a current-constrained approach to achieve a steady-state condition where spin current and spin polarization can be directly observed. The connectivity of the system, the role of SOC and the electron correlation, the molecular vibrations are critically discussed.