Spin and charge transport in chiral materials from first-principles temporal-spatial density matrix dynamics

The phenomenon of chiral-induced spin selectivity (CISS) has gained significant interest due to the ability of chiral nonmagnetic materials to generate spin-polarized currents through running charges without external magnetic fields. However, the microscopic picture of intricate interplays among structural chirality, spin, orbital, and phonon angular momentum (AM) is still illusive. For example, how AM is transferred to spin from orbital or phonon AM is under debate. In this work, we employ our recently developed computational framework that combines first-principles density-matrix dynamics including quantum scatterings such as electron-phonon coupling with self-consistent spin-orbit coupling, with semi-classical spatial transport via the Wigner function formalism. We investigate coherent and incoherent transport in chiral materials, through which we calculate spin polarization. We then analyze the underlying mechanism of AM transfer among the different degrees of freedom in chiral Se. Our findings reveal the mechanism of CISS in chiral crystals and offer design principles for materials with optimal CISS and novel spintronic devices with efficient spin and orbital manipulation.