Narrowband and Broadband Dual‐Mode Perovskite Photodetector for RGB Detection Application

Abstract

Wavelength‐selective light detection is becoming more and more prevalent as new sectors emerge, such as imaging, wearable electronic devices, the Internet of Things, machine vision, and biosensing. Traditional narrowband RGB detection necessitates several separate devices for different colors by changing the active layer materials or applying color filters ahead of the broadband detector, which increases the architectural complexity and limits the quality of color sensing. Here, this work devises a novel dual‐mode perovskite photodetector with both narrowband and broadband light sensing based on the imbalance transportation of carriers in the perovskite: Rhodamine B (RhB) active layer. In Mode 1, under light illumination from ITO, a narrowband response in 600–700 nm is obtained with a specific detectivity (D*) of 6.7 × 1011 Jones, responsivity (R) of 7.6 mA W−1, and a full‐width at half‐maximum (FWHM) of 80 nm. In Mode 2, under light illumination from Ag, the visible broadband response of 400–700 nm is achieved with a D* of 1012 Jones and R over 80 mA W−1. Furtherly, by designing a simple optical system and signal processing, RGB light signals are detected independently and panchromatic image sensing and rebuilding are realized. This work will give inspiration to architecture design for multi‐band integrated photodetectors.