Fabrication of Terahertz YBa2Cu30,-s Hot-Electron Bolometer Mixers

Superconducting hot-electron bolometer (HEB) mix- ers are promising heterodyne detectors for THz frequencies. HEB mixers operating at 4 K or below offer the possibility of near-quantum-limited performance without an upper frequency limit imposed by the superconducting energy gap. High tem- perature superconductor HEB mixers offer very sensitive, low power heterodyne detectors operating at temperatures ap- proaching 90 K for applications requiring closed-cycle refrigera- tion. We report on recent progress in fabricating and charac- terizing high-T, mixers based on ultra-thin (10-20 nm) YBazCu3O7.6 films patterned to submicrometer dimensions (0.1-1 ym) and incorporated into 1-3 THz planar mixer circuits.