Morphology engineering of a hybrid perovskite for active terahertz memory modulation

Morphology engineering was investigated for hybrid perovskites CH₃NH₃PbI₃:Ag/Poly(3, 4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) that were fabricated in both air and nitrogen environments for active terahertz (THz) memory modulation. Under low optical excitation or an applied bias, THz amplitude modulation or rapid restore in both CH₃NH₃PbI₃:Ag/PEDOT:PSS hybrid structures were demonstrated. The recovery time of the modulated THz wave in the sample fabricated in air was considerably longer than that of the sample fabricated in nitrogen because of defect states induced by a high degree of roughness. THz transmissions were used as coded pixel units and were programmed to store a 4×4 image or a multi-order signal. Hence, active THz memory modulation was demonstrated. It also has potential applications as a visible to near-infrared broad-spectrum light detector.