High-TC THz HEB mixers: Progress and prospects

We analyze the pathways for achieving the THz hot-electron bolometer (HEB) mixers using high-T_C superconductors. Requirements to the material in order to obtain large (up to 10 GHz) intermediate frequency bandwidth as well as recent results on MgB₂ HEB mixer devices are discussed. Based on a thermal model of the energy relaxation in a thin film, we explain the difference between the mixing behaviors in previously studied HEB materials. We also introduce the concept of the HEB mixer based on the low electron density MBE-grown quasi-2DEG LaCuO/LaSrCuO superconductors with tunable critical temperature.