Self-Powered Polarization-Sensitive 3D Photodetector with Fast Response Enabled by Mechanically-Guided Assembly of Tubular MoS2/GaAs/InGaAs Heterostructure

Abstract

3D photodetectors (3dPDs) fabricated by mechanically-guided assembly have garnered significant attention for their unique structures and photodetection capabilities. However, 3dPDs constructed with heterostructures still face major challenges and have yet to demonstrate self-powered polarization-sensitive photodetection, owing to the extreme difficulties in 3D assembly of heterostructures and the fabrication of perfectly-matched electrodes. In this study, self-powered polarization-sensitive 3dPDs based on heterostructures have been demonstrated for the first time through the controllable rolling assembly and crafted electrode design of tubular MoS₂/GaAs/InGaAs heterostructure. A dichroic ratio of 1.39 is measured under 650 nm wide-angle omnidirectional incident light, and the underlying polarization mechanism is clearly elucidated through comparative experiments and simulations, primarily attributed to the uniaxially-strained MoS₂ in the self-rolled-up heterostructure. Benefiting from the built-in electric field offered by the heterostructure, the as-fabricated self-powered 3dPD demonstrates a fast response time (τ_r/τ_f) of 710/700 µs, which is nearly two orders faster than the self-powered polarization-sensitive tubular 3dPD based on homostructures, meanwhile achieving a responsivity of 86 mA W⁻¹. Significantly-improved polarization-sensitive photodetection performance of heterostructure-based self-powered 3dPDs can be expected via introducing functionalized 2D materials and semiconductors, thus making tubular 3dPDs great application prospects in low-power consumption, fast recognition, and target tracking.