Beijing researchers develop ultra-sensitive infrared detector using dual-phase molybdenum ditelluride for advanced machine vision

Beijing researchers use stacked MoTe2 phases to create an ultra-sensitive infrared detector that sees light polarization without filters.

By: AXL Media

Published: Apr 16, 2026, 8:04 AM EDT

Source: Information for this report was sourced from Editorial Office of Opto-Electronic Journals Group

A New Dimension for Machine Perception

Researchers from Beijing Information Science and Technology University, in collaboration with Tsinghua University and RMIT University, have developed a revolutionary near-infrared (NIR) photodetector that grants machines a sensory capability beyond human vision. Published in Opto-Electronic Advances, the study details a device that can detect not only the brightness and color of light but also its polarization direction and invisible infrared wavelengths. Professor Lianqing Zhu, a lead researcher on the project, states that this technology serves as a fundamental building block for future sensing systems, allowing machines to decipher complex environmental information such as surface textures and material compositions.

The Innovation of Homologous Polymorphic Junctions

The core technical breakthrough lies in a novel materials science strategy that utilizes two different structural phases of a single chemical compound, molybdenum ditelluride (MoTe2). Instead of layering two different materials, which can create interface defects, the team stacked the semimetallic 1T' phase and the semiconducting 2H phase of MoTe2 with atomic precision. This "homologous polymorphic heterojunction" creates a natural electronic alignment that acts as a rapid charge sorter. When infrared light hits the device, this internal field efficiently separates light-generated charges, resulting in a significantly stronger electrical signal and higher sensitivity than traditional detectors.

Broad Spectrum Sensitivity and Performance

The fabricated device demonstrated exceptional performance across a wide optical range, spanning from visible light at 532 nm to short-wave infrared at 2200 nm. Testing under a 1310 nm near-infrared laser revealed a high responsivity of 3.06 A·W–1 and an external quantum efficiency of 289%. These metrics indicate a superior ability to convert photons into electrical signals. Additionally, the detector proved capable of rapid signal processing with a rise time of approximately 10.56 milliseconds, making it a viable candidate for high-speed applications such as autonomous driving and real-time environmental monitoring.