Applied Physics Letters

Submillimeter wave responses in NbN/AlN/NbN tunnel junctions

Yoshinori Uzawa, Zhen Wang, Akira Kawakami, Bokuji Komiyama

Published Apr 10, 1995• 19 citations

Abstract

The submillimeter wave frequency responses of NbN/AlN/NbN tunnel junctions have been investigated using quasioptical coupling techniques and an optically pumped far-infrared laser. A two junction array was integrated at the feeds of a bowtie antenna. Measurements on the junctions were made by monitoring photon-assisted tunneling steps induced in the current–voltage characteristics. These n=±1 photon steps were clearly observed with irradiation at 303, 594, 693, and 762 GHz. The results suggest it will be possible to realize submillimeter wave mixers by using these junctions.

DOI: 10.1063/1.113672

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