High Speed Nanoantenna Thermopiles for Long-Wave Infrared Detection

We study thermoelectric signal generation by suspended nanoantenna thermopiles in response to amplitude-modulated long-wave infrared radiation. We experimentally demonstrate response times on the order of a few μs with a signal bandwidth of about 200 kHz. Analytical calculation and simulation results show that the limiting factor of the response time is not the inverse RC time constant of the array but rather the thermal response of the nanostructure.