Chiral-Induced Spin Selectivity in Photon-Coupled Achiral Matters

Chiral-induced spin selectivity is a phenomenon in which electron spins are polarized as they are transported through chiral molecules, and the spin polarization depends on the handedness of the chiral molecule. In this study, we show that spin selectivity can be realized in achiral materials by strongly coupling electrons to a circularly polarized mode of an optical cavity or waveguide. Through the investigation of spindependent electron transport in a two-terminal setup using the nonequilibrium Green's function approach, it is found that a large spin polarization can be obtained if the rate of dephasing is sufficiently small and the average chemical potential of the two leads is within an appropriate range of values, which is narrow because of the high frequency of the optical mode. To obtain a wider range of energies for a large spin polarization, chiral molecules can be combined with light-matter interactions. To demonstrate this, the spin polarization of electrons transported through a helical molecule strongly coupled to a circularly polarized optical mode is evaluated.

Automated summary

Chiral-induced spin selectivity is a phenomenon where electron spins are polarized based on the handedness of chiral molecules. This study shows that spin selectivity can be achieved in achiral materials by coupling electrons to a circularly polarized mode of an optical cavity or waveguide. By investigating spin-dependent electron transport using the nonequilibrium Green's function approach, it is found that a large spin polarization can be obtained under specific conditions. Additionally, combining chiral molecules with light-matter interactions can provide a wider range of energies for spin polarization.