Perovskite‐based time‐domain signal‐balancing LiDAR sensor with centimeter depth resolution

Abstract A novel class of semiconducting compounds, metal‐halide perovskites (MHPs), has emerged as a versatile platform for advanced optoelectronic device architectures, offering a unique combination of exceptional physical properties and facile processing. In this study, we present a monolithic high‐speed photodetector capable of directly sensing the time delay between two light pulses with a temporal resolution of at least 170 ps, corresponding to a light propagation distance of ~5 cm—making it well suited for Light Detection and Ranging (LiDAR) applications. This outstanding time resolution is achieved through a signal‐balancing detection scheme that effectively overcomes the limitations of conventional photodetectors, whose response speed is inherently limited by charge‐carrier lifetime and transit time. The device exhibits an exceptionally low noise spectral density, comparable to that of state‐of‐the‐art silicon photodiodes. The fully symmetric device stack comprises a crystalline CsPbBr ₃ absorber layer tens of microns thick, fabricated via a confined melt process. Comprehensive electro‐optical characterization reveals charge‐carrier lifetimes and mobilities on both microscopic and macroscopic length scales, using transient photoluminescence, time‐resolved photocurrent, time of flight, and terahertz pump–probe spectroscopy. The CsPbBr ₃ layer exhibits charge‐carrier lifetimes exceeding 100 ns, a microscopic electron–hole mobility of 15 ± 1 cm ² V ⁻¹ s ⁻¹ , and a macroscopic non‐dispersive hole mobility of 8.5 cm ² V ⁻¹ s ⁻¹ . image