The chiral induced spin selectivity effect – dissipation and breaking the chiral symmetry

The chiral induced spin selectivity (CISS) effect originates from structural chirality and offers a route to provide strongly spin-polarized currents and localized magnetic moments, based on organic molecules only without incorporation of magnetic elements or metals. While there are numerous reproductions of the result experimentally, the theoretical understanding is yet based on effective modeling where various origins of the effect have been suggested. It is, however, indisputable that chirality and spin-orbit coupling are connected. For the emergence of spin-dependent effects, time-reversal symmetry has to be broken and I will discuss possible, viable, and dissipation based mechanisms that break time-reversal symmetry. Furthermore, the spin-degeneracy breaks due to broken chiral symmetry. The combination of those conditions leads to the CISS effect. Moreover, using a simple effective model for a generic set-up pertaining to transport measurements of the CISS effect, several features observed in experiments can be explained.