Title :
Modulation of self-resonant modes in NbCN/MgO/NbCN junctions by quasiparticle injection
Author :
Kohjiro, S. ; Kiryu, S. ; Shoji, A. ; Kodaira, S. ; Takada, S.
Author_Institution :
Electrotech. Lab., Tsukuba, Japan
fDate :
6/1/1995 12:00:00 AM
Abstract :
In the submillimeter wave region, we have studied the modulation of self-resonant modes in NbCN/MgO/NbCN Josephson junctions (detectors). The tuning mechanism is based on the quasiparticle injection via an overlaid tunnel junction (injector). From the current-voltage characteristics of detectors, the maximum shift of resonant frequencies /spl Delta/f and Q factors due to electrode loss at the injected state Q/sub inj/ have been estimated to be /spl Delta/f/f(0)=0.11 and Q/sub inj/=100 at 470 GHz, where f(0) is the resonant frequency without quasiparticle injection. It is found Q/sub inj/ decreases with increase of the injector bias voltage.<>
Keywords :
Josephson effect; Q-factor; magnesium compounds; niobium compounds; quasiparticles; submillimetre wave detectors; superconductor-insulator-superconductor devices; 470 GHz; NbCN-MgO-NbCN; NbCN/MgO/NbCN Josephson junctions; Q factors; current-voltage characteristics; electrode loss; modulation; quasiparticle injection; self-resonant modes; submillimeter wave detectors; tuning; tunnel junction; Current-voltage characteristics; Detectors; Electrodes; Frequency estimation; Josephson junctions; Q factor; Resonant frequency; State estimation; Tuning; Voltage;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
