  We present a non-perturbative theory that describes how light regulates
chiral-induced spin selectivity (CISS) from the perspective of strong
light-matter interactions. The research results indicate that 1) light can have
opposite effects on the CISS, 2) the difference in CISS is caused by the steady
states of nuclei coupled to spin electrons and 3) this steady state differences
are caused by the different light-induced Lorentz forces felt by spin-up and
spin-down electrons. The fundamental reason for these results is the impact of
light on spin-orbital coupling (SOC), which is a complex process. This
theoretical framework is verified by the calculations of Floquet SOC
non-adiabatic nuclear dynamics.
