A visible‐to‐infrared miniaturized indium selenide spectrometer enabled by a gate‐tunable spectral response matrix

Two‐dimensional heterostructure‐based computational spectrometers with broad operational bandwidths demonstrate significant potential for laboratory and industrial applications, including medical diagnostics, chemical analysis, and environmental monitoring. However, the fabrication difficulty of two‐dimensional heterostructures hinders their practical and scalable applications. Multilayer indium selenide (InSe), with its high carrier mobility (>10 3 cm 2 V −1 s −1 ) and direct bandgap of ∼1.3 eV, is a promising candidate for high‐performance broadband spectrometers. Here, we develop a homostructure InSe spectrometer, combining advanced computational spectral‐reconstruction algorithms with a gate‐tunable spectral response matrix to demonstrate a room‐temperature InSe‐based spectrometer with a broad operational bandwidth ranging from 450 to 973 nm. The device features a miniaturized footprint of approximately 20 × 50 μm 2 , achieves nanometer‐level resolution (<0.33 nm), and operates at low voltages ranging from −4 to+4 V. Our work paves the way for high‐performance computational spectrometers with diverse applications, including sensing, surveillance, proof‐of‐concept spectral imaging, and spectral measurements.