Terehertz-Infrared Microsphere Bolometer

To address the Army"s need for an ultra-sensitive, room-temperature, long-wavelength radiation detector, Physical Optics Corporation (POC) proposes to develop a new Terahertz-Infrared Microsphere Bolometer (TIMBol). This proposed device is based on thermally induced wavelength shifts of whispering gallery mode (WGM) resonances in high quality factor microspheres. The innovation in thermal and optical isolation, WGM interrogation, and optical cooling will enable the device to achieve ultra-sensitive THz and IR detection. As a result, the new device offers a noise equivalent power (NEP) of better than 10^-13 W without cooling, and will be further optimized with the potential to exceed liquid helium cooled bolometers. These specifications directly address the Army"s requirements to eliminate increasingly expensive consumables such as liquid helium. In Phase I, POC will demonstrate the feasibility of its TIMBol technology by illuminating the detector with a THz source and reducing the incident THz power using high optical density (OD) fused silica filters to the lowest detectable light level. In Phase II, POC plans to develop single channel and array prototypes.