Spin control in reduced-dimensional chiral perovskites

Hybrid organic–inorganic perovskites exhibit strong spin–orbit coupling 1 , spin-dependent optical selection rules 2 , 3 and large Rashba splitting 4 – 8 . These characteristics make them promising candidates for spintronic devices 9 with photonic interfaces. Here we report that spin polarization in perovskites can be controlled through chemical design as well as by a magnetic field. We obtain both spin-polarized photon absorption and spin-polarized photoluminescence in reduced-dimensional chiral perovskites through combined strategies of chirality transfer and energy funnelling. A 3% spin-polarized photoluminescence is observed even in the absence of an applied external magnetic field owing to the different emission rates of σ + and σ − polarized photoluminescence. Three-dimensional perovskites achieve a comparable degree of photoluminescence polarization only under an external magnetic field of 5 T. Our findings pave the way for chiral perovskites as powerful spintronic materials. Spin-polarized photon absorption and photoluminescence are reported in reduced-dimensional chiral perovskite materials. The finding indicates that such materials may in the future be useful as a photonic interface for spintronics.