Nanowatt Thermal Radiation Sensing using Silicon Nitride Nanomechanical Resonators

Nanomechanical resonators are immune to electrical Johnson noise [1], making them a promising solution for infrared and terahertz radiation sensing beyond the performance of traditional thermal sensors [2] (e.g., bolometers). Here, we demonstrate detection of thermal radiation using thin (100 nm), large area (3 mm × 3 mm) SiN membrane resonators at room temperature. Our measurements demonstrate a detection limit on the order of 1 nW, with a characteristic response time of 85 ms. These preliminary measurements are comparable to state-of-the art commercial thermal sensors of similar surface area and response time (e.g., 5 nW detection limit reported in [3]).