Operation of YBCO kinetic-inductance bolometers for outer solar system missions

Abstract

We developed superconducting kinetic inductance bolometers (KIBs) for hyperspectral imaging in outer solar system missions. Each bolometer is a microwave L-C resonator that will act as an individual pixel in the focal plane of an imaging Fourier transform infrared spectrometer. Our devices are fabricated from high temperature superconductor yttrium barium copper oxide (YBCO), with a superconducting transition temperature of ∼85 K. The inductors are suspended on thin Si3N4 membranes. Each resonator operates at a unique resonant frequency, and hence, many can be multiplexed on a single feed line using a large number of carrier frequencies. The resonators function as detectors because their resonant frequencies decrease with increasing temperature as the bolometers absorb incident radiation. In this paper, we discuss the thermal properties of a YBCO KIB and its response to signal power to verify that the response is near theoretical predictions.