학술논문
A 547 GHz SIS receiver employing a submicron Nb junction with an integrated matching circuit
Document Type
Conference
Author
Source
1993 IEEE MTT-S International Microwave Symposium Digest Microwave Symposium Digest, 1993., IEEE MTT-S International. :771-774 vol.2 1993
Subject
Language
ISSN
0149-645X
Abstract
A heterodyne receiver using an SIS (superconductor-insulator-superconductor) waveguide mixer with two mechanical tuners has been built and characterized over the frequency range of 460 GHz to 630 GHz. This receiver is designed for radioastronomy applications. The mixer uses high-current-density, 0.25- mu m/sup 2/, Nb/AlO/sub x//Nb SIS tunnel junctions with integrated superconductive RF circuits to tune the junction capacitance. A DSB (double sideband) receiver noise temperature as low as 200+or-17 K has been obtained at 540 GHz. In addition, negative differential resistance has been observed in the DC I-V (current-voltage) curve at 487-491 GHz.ETX