MnBi2Te4 Thin-Film Photodetector with a Millisecond Response Speed and Long-Term Air Stability

Abstract

Topological materials with well-defined surfaces and edges have become a prominent research topic. As topological insulators, MnBi2Te4 thin films, with their unique surfaces, exhibit exceptional electron transport properties and good applicability in low-noise, high-sensitivity photoelectric detection. This paper reports a straightforward, efficient, and cost-effective thermal evaporation method for preparing quantum MnBi2Te4 thin films, along with an investigation into their photoelectric detection performance. These films can be used to fabricate array devices, with the resulting photodetectors achieving a response current of 97 mA W−1 at room temperature and a response speed of <1 ms. Moreover, they demonstrate stability in the air for >30 d, with the photoelectric performance degrading by <15%. Our research introduces a new application for topological materials in photoelectric detection and establishes a strong foundation for the design and development of high-performance photodetectors in the future.