Bin Hu1
University of Tennessee1
Hybrid metal halide perovskites are known as emerging semiconducting materials with tunable structure-property relationships through solution-processing methods. Such solution-processing perovskites simultaneously carry spin and orbital momentum. Consequently, using spin and orbital momentum has become a critical approach to control the multifunctional properties. However, characterizing spin and orbital parameters still demands much effort to understand their underlying relations to materials properties. To respond to this demand, we have been using magnetic field effects and circularly polarized laser spectroscopy to experimentally investigate spin and orbital parameters in determining light-emitting, photovoltaic, and lasing properties in hybrid metal halides. Our magnetic field effects have shown that bright and dark excitons are having largely different outcomes when generating optic, electric, optoelectronic actions. Therefore, magnetic field effects provide an essential experimental tool to characterize spin effects in such solution-processing perovskites. Furthermore, we found that circularly polarized luminescence can be used as a convenient method to elucidate orbital dynamics within Rashba band structures. We discovered that the circularly polarized orbitals with right and left handedness in Rashba band structures can selectively interact with spin-up and spin-down spin dipoles, leading to a mutually selectivity between spin order and orbital order. Particularly, this selective interaction between spin order and orbital order can enable spin-switchable phenomena towards developing emerging functionalities in these solution-processing hybrid metal halide perovskites. This presentation will discuss the fundamental details on exploring spin and orbital parameters by using magnetic field effects and circularly polarized laser spectroscopy.