Ultrasensitive Perovskite Photodetector for Filter‐Free Color Single‐Pixel Imaging

Abstract

Filter‐free color imaging is the long‐pursued solution for its simple structure, low cost, and high stability. However, a spectroscopic unit is still necessary for the current Si‐based imaging unit due to the intrinsic photoresponse properties of Si. Here, the authors demonstrate a filter‐free color‐resolved single‐pixel imaging (SPI) by combining the working mechanism of computational ghost imaging and the response characteristic of perovskite. Benefitting from a broad linear dynamic range (106.5 dB) and a high detectivity (4.03 × 1014 Jones) of the fabricated ultrasensitive MAPbBr3 microwire arrays (MWAs) photodetector, the light attenuation caused by an object can be effectively correlated with its color. The reconstructed images of both transmissive and reflective color objects show a high wavelength resolution reaching 20 nm in the range of 400–540 nm, which is impossible to achieve by commercial silicon‐photodiode‐based ones. This work can open a new door for the image acquisition of color‐sensitive objects and also pave a way for the evolution of the next generation of detectors and cameras with low‐dimensional perovskite materials.

A photo-switchable rectifier based on the MAPbBr3–MAPbCl3 halide perovskite heterostructure for dual-wavelength optical communications

“…Only the first three orders of diffractions from the (100) planes can be observed in both cases, and full width at a half maximum (FWHM) values of 0.048° and 0.054° for MAPbBr 3 and MAPbCl 3 of the 200 diffraction peaks were obtained, which are consistent with or even smaller than those reported for single crystals based on cubic ( Pm 3̄ m ) perovskite structures. 35–37 The scanning electron microscopy (SEM) image in Fig. 1b displays the cleaved cross-section of the MAPbBr 3 /MAPbCl 3 heterostructure, which shows that the two crystals are tightly bonded together without any observable voids in between.…”

Zero-bias Bi-based perovskite image sensor arrays with direct laser-scribing process

“…The calculated value of E VBM is 6.14 eV, and the work function is 4.18 eV. Based on the absorption spectrum of Cs 3 Bi 2 Br 9 , we calculated the optical bandgap of the Cs 3 Bi 2 Br 9 films using the Tauc method: 43 ( α · hv ) 2 = B ·( hv − E g )where α is the absorption coefficient, hv is the photon energy, h is Planck's constant, B is the proportionality constant, and E g is the band gap of the semiconductor material. The Tauc plot (Fig.…”

Recent progress in construction methods and applications of perovskite photodetector arrays

“…A photodetector, as a device that converts optical signals into electrical signals, possesses widespread applications in optical communication, 31,32 digital imaging, 33–35 bionics, 36–38 and artificial electronic skin. 39,40 In recent years, metal halide perovskites have revolutionized photodetector performances, such as detectivity, 41–43 response speed, 44–46 and on/off ratio.…”