Plasmonic Resonance Enabling 2D Perovskite Single Crystal to Detect Telecommunication Light

摘要

High performance photodetectors (PDs) based on two-dimensional (2D)perovskite single crystals (SCs) have been demonstrated with improvedstability with respect to those based on their three-dimensional counterparts.However, due to their large energy band gaps, response of 2D perovskitePDs is limited in the ultraviolet and visible range. In this study, a broadbandPD based on (PEA)_2PbI_4 (PEA = C_6H_5(CH_2)_2NH~(3+)) 2D perovskite SC isdemonstrated by incorporating thermally annealed Au nanoparticles (NPs).Introduction of Au NPs brings forward enhancement in photocurrent overa broadband wavelength range with the dark current being maintained.In the light absorption range of (PEA)_2PbI_4, photocurrent enhancement isowing to the enhanced localized electric field induced by Au NPs. Beyond the(PEA)_2PbI_4 absorption range of 650–900 nm, the photocurrent enhancementfactors reach 1000 in average, which arises from the hot holes produced byAu NPs. It is also emphasized that the response wavelength of the PD hasbeen extended to the telecommunication band; specifically, the light signalsat 1310 nm can be converted to stable on-off electric signals by the plasmonicPD. This work promotes the development of broadband, sensitive solutionprocessedperovskite PDs, providing a promising strategy for realizing photodetectionin the telecommunication range.