A fast uncooled infrared nanobolometer featuring a hybrid-plasmonic cavity for enhanced optical responsivity

We demonstrate the first uncooled single-nanowire-based infrared bolometer to detect sub-mW optical signals up to MHz frequencies. The bolometer consists of a Pt nanowire on a suspended silicon hybrid-plasmonic cavity, and exhibits enhanced optical responsivity compared to nanowires on unstructured and non-suspended substrates. Low-cost monolithically integrated infrared detectors are needed for the rapidly growing field of silicon photonic sensors. The high speed of our nanobolometer enables advanced modulation schemes for noise reduction and avoidance of low-frequency thermal cross-talk, as well as power saving by pulsed operation. Furthermore, its simple integration and small footprint make it a cost effective detector for sensing applications.