Hotspot mixing: a new principle of heterodyne mixing in a superconducting hot-electron bolometer

We present the hotspot mixing as a new principle of heterodyne mixing in a superconducting hot-electron bolometer. Applying DC and LO powers to a superconducting bridge generates a hotspot within the bridge. The size of the hotspot, and thus the resistance of the bridge, oscillates with the heating power at intermediate frequency. By solving heat-conducting equations, we can predict the mixer performances, such as the conversion efficiency, as a function of dc bias voltage, LO power, or the bath temperature