A Simple-Structured Perovskite Wavelength Sensor for Full-Color Imaging Application

In this study, simple-structured wavelength sensors were developed by depositing two back-to-back Au/MAPbI₃/Au photodetectors on an MAPbI₃ single crystal. This sensor could quantitatively distinguish wavelengths. Further device analysis showed that both photodetectors possess entirely disparate optoelectronic properties. Consequently, the as-developed wavelength sensor could accurately distinguish incident-light wavelengths ranging from 265 to 860 nm with a resolution of less than 1.5 nm based on the relation between the photocurrent ratios of both photodetectors and the incident light wavelengths. Notably, a high resolution and wide detection range are among the optimum reported values for such sensors and enable full-color imaging. Furthermore, technology computer-aided design (TCAD) simulations showed that a mechanism involved in distinguishing wavelengths is attributed to the wavelength-dependent photon generation rate in MAPbI₃ single crystals. The high-performance MAPbI₃ wavelength sensor can potentially drive the research progress of perovskites in wavelength recognition and full-color imaging.