Optomechanical metamaterial nanobolometer

Abstract

Bolometers are detectors of electromagnetic radiation that usually convert the radiation-induced change in temperature of the detector into electric signals. Temperature-dependent electrical resistance in semiconductors and superconductors, the thermoelectric effect in thermocouples, and the pyroelectric effect of transient electric polarization of certain materials when they are heated or cooled are among the underlying physical phenomena used in bolometers. Here, we report that the dependence of the fundamental frequency of a nanowire string detected via scattering of light on the string can be used in a bolometer. Arrays of such nanowires can serve as detectors with high spatial and temporal resolution. We demonstrate a bolometer with 400 nm spatial resolution, 2–3 µs thermal response time, and optical power detection noise floor at 3–5 nW/Hz1/2 at room temperature.