Bidirectional-Sensitive Dual-Narrowband Self-Powered Single Perovskite Photodetector for Fast Computational Imaging

Abstract

Narrowband photodetectors (PDs) are extensively utilized in fields such as image sensing, machine vision, and optical communications. Traditional approaches to achieving wavelength-selective light detection typically involve methods such as voltage-modulated charge collection or injection the incorporation of optical filters, or the use of multi-stacked active layer materials. Herein, an innovative dual-mode perovskite PD characterized by unbalanced charge carrier transport (UCCT) properties are introduced. By altering the direction of light incidence, the PD exhibits two distinct narrowband spectral responses, thereby significantly simplifying conventional strategies that complicate PD fabrication. This novel approach also mitigates issues related to slow response times, limited band selectivity, and low external quantum efficiency (EQE). In the Red (R)-Mode, a detection peak at 700 nm is identified, with a full-width at half-maximum (FWHM) of 30 nm, a specific detectivity (D*) of 2.6 × 1010 Jones, and a responsivity (R) of 179 mA W−1. Conversely, in Green (G-Mode, a narrowband response is observed with a peak at 500 nm, a FWHM of 75 nm, a D* of 1.1 × 1010 Jones, and an R of 75 mA W−1. Furthermore, a dual-mode narrowband single-PD imaging prototype, integrated with an advanced Fourier imaging algorithm, has been developed, enabling the reconstruction of high-quality images with 128 × 128 pixels within a time frame of 100 seconds. This research represents a significant advancement in the realm of filter-free dual-mode narrowband PDs and lays the groundwork for the evolution of next-generation optoelectronic applications.