Frequency- and Power-Dependent Photoresponse of a Perovskite Photodetector Down to the Single-Photon Level

Abstract

Organometallic halide perovskites attract strong interests for their high photoresponsivity and solar cell efficiency. However, there was no systematic study of their power-and frequencydependent photoresponsivity. We identified two different powerdependent photoresponse types in methylammonium lead iodide perovskite (MAPbI 3 ) photodetectors. In the first type, the photoresponse remains constant from 5 Hz to 800 MHz. In the second type, absorption of a single photon can generate a persistent photoconductivity of 30 pA under an applied electric field of 2.5 × 10 4 V/ cm. Additional absorbed photons, up to 8, linearly increase the persistent photoconductivity, which saturates with the absorption of more than 10 photons. This is different than single-photon avalanche detectors (SPADs) because the single-photon response is persistent as long as the device is under bias, providing unique opportunities for novel electronic and photonic devices such as analogue memories for neuromorphic computing. We propose an avalanche-like process for iodine ions and estimate that absorption of a single 0.38 aJ photon triggers the motion of 10 8−9 ions, resulting in accumulations of ions and charged vacancies at the MAPbI 3 /electrode interfaces to cause the band bending and change of electric material properties. We have made the first observation that single-digit photon absorption can alter the macroscopic electric and optoelectronic properties of a perovskite thin film.

Narrowband Near-Infrared Perovskite/Polymer Hybrid Photodetectors

“…The halide perovskite materials have a strong light absorption in the visible light range. The discrete perovskite PDs exhibit a broadband photoresponse over the visible wavelength range and a faster transient photoresponse due to the high charge carrier mobility . Enhanced omnidirectional photoresponse in photonic-structured perovskite PDs over the long-wavelength range has also been demonstrated .…”

“…The discrete perovskite PDs exhibit a broadband photoresponse over the visible wavelength range and a faster transient photoresponse due to the high charge carrier mobility. 13 Enhanced omnidirectional photoresponse in photonic-structured perovskite PDs over the long-wavelength range has also been demonstrated. 14 The absorption of the low band gap photoactive polymers, including the newly developed polymer donors, nonfullerene acceptors, and their blends, can be tailored extending to the near-infrared (NIR) wavelength range.…”

Recent Progress of Optoelectronic and All‐Optical Neuromorphic Devices: A Comprehensive Review of Device Structures, Materials, and Applications

“…[ 45 ] Oxide‐based perovskite materials can also be promising material candidates for optoelectronic neuromorphic devices because of their decent light‐response characteristics. [ 85 ] Bera et al reported a vertical structure light‐switchable memory device using Wurtzite ZnO on perovskite SrTiO 3 . [ 86 ] When the device was applied with UV light ( λ = 365 nm and power intensity of 2.5 mW cm −2 ), photogenerated, electrons were trapped, leading to a high conductance state.…”

Controlling screw dislocation evolution towards highly homogeneous quasi-two-dimensional (BA)2(MA)n−1PbnI3n+1 single crystals for high-response photo-detectors

“…The three-dimensional (3D) methylammonium lead iodide (MAPbI 3 ) perovskite is widely applied in various optoelectronic devices such as sensitized solar cells, photo-detectors, lasers, and light emitting diodes and in catalysis [1][2][3][4][5][6][7][8][9][10] due to its direct band gap, long carrier migration, high light absorption coefficient, and high defect tolerance. [11][12][13][14][15][16][17][18][19] Recently, the power conversion efficiency (PCE) of perovskite solar cells has exceeded 25.5%, comparable to that of silicon solar cells.…”