Stimulating and Manipulating Robust Circularly Polarized Photoluminescence in Achiral Hybrid Perovskites

Abstract

Circularly polarized light (CPL) is essential for optoelectronic and chiro-spintronic applications. Hybrid perovskites, as star optoelectronic materials, have demonstrated CPL activity, which is, however, mostly limited to chiral perovskites. Here, we develop a simple, general, and efficient strategy to stimulate CPL activity in achiral perovskites, which possess rich species, efficient luminescence, and tunable bandgaps. With the formation of van der Waals heterojunctions between chiral and achiral perovskites, a nonequilibrium spin population and thus CPL activity are realized in achiral perovskites by receiving spinpolarized electrons from chiral perovskites. The polarization degree of room-temperature CPL in achiral perovskites is at least one order of magnitude higher than in chiral ones. The CPL polarization degree and emission wavelengths of achiral perovskites can be flexibly designed by tuning chemical compositions, operating temperature, or excitation wavelengths. We anticipate that unlimited types of achiral perovskites can be endowed with CPL activity, benefiting their applications in integrated CPL sources and detectors.

Dynamically stable and amplified circularly polarized excimer emission regulated by solvation of chiral co-assembly process

“…In the past several years, much work has focused on circularly polarized luminescence (CPL) materials because of their potential applications in 3D optical displays, information encryption, and chiral sensing 1 – 5 . These sophisticated CPL-active materials inevitably involve two common problems—their low quantum yield ( Ф FL ) and the luminescence dissymmetry factor ( g em ).…”

Metal halide perovskites: promising materials toward next-generation circularly polarized luminescence

“…Based on perovskites with greater SOC characteristics and CISS effects, for achiral organic ammonium MHPs materials, the development of new strategies such as regulating spin electrons, upconversion-induced fluorescence, and chiral energy transfer. 97,131 New strategies need to be developed as a breakthrough point to improve the low | g CPL | and low CD intensity of MHP materials.…”

Spin-polarized excitons and charge carriers in chiral metal halide semiconductors

“…An aqueous phase synthesis method 50 was used by adding a small proportion of MA + during the synthesis process, and MA + does not change the composition and structure of (R/S-MBA) 2 PbI 4 , but induces (R/S-MBA) 2 PbI 4 to produce a CPL signal at room temperature, which may be attributed to the passivation effect of the MA + additive and the average DP of (R-MBA) 2 PbI 4 and (S-MBA) 2 PbI 4 was 13.7% and 11.4%. 27 The CPL capability of (R/S-MBA) 2 PbI 4 27,51 and (R/S-1-(4-bromophenyl) ethyl-amine) 2 PbI 4 52 reaches DP > 10% at room temperature, but there is still plenty of room for DP to be improved up to the theoretical maximum DP value of 1.…”