One-step rolling fabrication of VO₂ tubular bolometers with polarization-sensitive and omnidirectional detection

Uncooled infrared detection based on vanadium dioxide (VO₂) radiometer is highly demanded in temperature monitoring and security protection. The key to its breakthrough is to fabricate bolometer arrays with great absorbance and excellent thermal insulation using a straightforward procedure. Here, we show a tubular bolometer by one-step rolling VO₂ nanomembranes with enhanced infrared detection. The tubular geometry enhances the thermal insulation, light absorption, and temperature sensitivity of freestanding VO₂ nanomembranes. This tubular VO₂ bolometer exhibits a detectivity of ~2 × 10⁸ cm Hz^1/2 W^-1 in the ultrabroad infrared spectrum, a response time of ~2.0 ms, and a calculated noise-equivalent temperature difference of 64.5 mK. Furthermore, our device presents a workable structural paradigm for polarization-sensitive and omnidirectional light coupling bolometers. The demonstrated overall characteristics suggest that tubular bolometers have the potential to narrow performance and cost gap between photon detectors and thermal detectors with low cost and broad applications.