NbZr films for THz phonon-cooled HEB mixers

摘要

This work is devoted to the investigation of the applicability of NbZr as a new material for wideband hot-electron bolometer (HEB) mixer, which is a device of choice for most of low noise heterodyne receivers operating above 1 THz in astronomy applications. Although currently 10-nm NbZr films offer a maximum gain bandwidth of only 450 MHz at T_c on sapphire substrates, there is every reason to believe that the above result can be improved by decreasing the film thickness and using other substrate material which will provide better acoustic match with NbZr.