Characterization of the IF Bandwidth of an All-NbN Superconductor-Insulator-Superconductor Mixer

Author

Liu, Deming ; Li, Jie ; Wang, Zhen ; Yao, Minli ; Hu, Jiankun ; Shi, S.C.

Author_Institution

Key Lab. of Radio Astron., Purple Mountain Obs., Nanjing, China

Volume

23

Issue

3

fYear

2013

fDate

Jun-13

Firstpage

1400504

Lastpage

1400504

Abstract

Large intermediate-frequency (IF) bandwidth is of particular interest for heterodyne mixers, especially for those at THz frequencies. NbN superconductor-insulator-superconductor (SIS) junctions, with a gap frequency twice that of Nb, can be applied to mixers beyond 1 THz. The IF bandwidth of NbN SIS mixers, however, is yet to be fully understood. In this paper, we investigate the IF bandwidth of a 0.5 THz all-NbN SIS mixer. First, its IF bandwidth is numerically simulated in terms of the mixer conversion efficiency and time constant. Second, the mixer noise performance is experimentally characterized in the IF band of 0.5 ~ 12 GHz. Detailed theoretical simulation and experimental results will be presented.

Keywords

niobium compounds; submillimetre wave mixers; superconducting microwave devices; superconductor-insulator-superconductor mixers; type II superconductors; IF bandwidth; NbN; SIS mixers; THz frequencies; all-NbN superconductor-insulator-superconductor mixer; frequency 0.5 THz; heterodyne mixers; intermediate-frequency bandwidth; mixer conversion efficiency; mixer noise performance; superconductor-insulator-superconductor junctions; time constant; Bandwidth; Isolators; Junctions; Mixers; Noise; Receivers; Temperature measurement; Intermediate-frequency (IF) bandwidth; submillimeter; superconducting; superconductor-insulator-superconductor (SIS) mixer; tunneling junction;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/TASC.2012.2237493

Filename

6407819