Tunable Drift–Diffusion Synergy in Suspended Te Nanowires for Multistate Photodetection

作者：Ni Sheng, Cheng-Tang Pan, Xin Li, Fengyi Zhu, Shuangli Mi, Xuhao Fan, Rui Zhang, Xutao Zhang, Haibiao Guan, He Zhu, Jingzhou Li, Weiwei Tang, Haibo Shu, Changlong Liu, Guanhai Li, Xiaoshuang Chen · 发表于：Nano Letters · 年份：2025 · DOI：10.1021/acs.nanolett.5c00722 · 被引用次数：19 · 研究领域：Nanowire Synthesis and Applications、Advanced Thermoelectric Materials and Devices、Thermal Radiation and Cooling Technologies

Tuning the interplay between photoconductive (drift-driven) transport and photothermoelectric (diffusion-driven) transport in a single device remains crucial for next-generation optoelectronics and in-sensor computing. Here, we present a suspended tellurium nanowire (Te NW) photodetector that concurrently harnesses and actively balances these two transports using asymmetric (local) or symmetric (flood) illumination in tandem with a bias voltage. This enables on-demand transitions from diffusion-dominated to drift-dominated photoresponses at room temperature, a feat not realized in prior Te-based detectors. Under zero bias with local illumination, robust photothermoelectric diffusion yields positive or negative photocurrents, with a responsivity R i of 124.28 A/W and specific detectivity ( D *) of 7.80 × 10 11 Jones. Conversely, flood illumination under finite bias triggers photoconductive drift, with a peak responsivity R i of 65.03–68.79 A/W and D * of 7.99 × 10 10 –8.47 × 10 10 Jones. By programming the illumination and bias conditions, we realize positive, negative, or zero photocurrent states, forming a three-mode response platform. Remarkably, the device exhibits a sub-100 μs response time and retains stable detection under ambient conditions, illustrating its viability for real-world applications. This work establishes a versatile blueprint for broadband, multistate photodetection toward in-sensor computing tasks.