Authors: Xiao Liu, Chuyun Deng, Hao Wei, Mengke Fang, Bo Yan, Tao Zhu, Shufang Luo, Gang Peng, Weiwei Cai, Mingsheng Long, Xueao Zhang
Published: 2025-03-11
Source: Full article
AbstractMid‐wave infrared (MWIR) sensing technology provides tremendous support for cutting‐edge applications in autonomous navigation, quantum information, and optical telecommunications. Recent researchers have reported substantial advancements in the MWIR photodetection based on 2D topological semimetal platinum selenide (PtSe2). However, its application prospect has been constrained by limited sensitivity and sluggish response speed. Herein, an uncooled MWIR photodetector integrating PtSe2 with MoTe2 is reported, which features high responsivity (R) of 8.4–2.5 A W−1 and specific detectivity (D*) of 4.5 × 109–1.3 × 109 cm Hz1/2W−1 from 2.75 to 4.25 µm. At 10.6 µm wavelength, it is still able to showcase a decent R of 0.12 A W−1. Notably, the photodetector achieves the brilliant photoresponse speed of 3–5 µs from visible to near‐infrared (NIR) spectral ranges with a competitive 3 dB frequency of 0.13 MHz. Meanwhile, a promising fast response speed of 560 µs is demonstrated at 4050 nm in MWIR range, which unveils its conspicuous ability to track ultrafast and broadband light signals. It might be attributed to the high carrier mobility and strong built‐in electric field at the PtSe2/MoTe2 interface. This research can provide a viable pathway for next‐generation room‐temperature MWIR photodetectors with high sensitivity and fast response speed.