The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 25, 1986
Filed:
Sep. 14, 1984
Nippon Telephone & Telegraph Public Corporation, Tokyo, JP;
Abstract
A photodetecting device having Josephson junctions, comprises an insulating substrate, a polycrystalline superconductor film formed on the insulating substrate such that Josephson junctions are formed at grain boundaries, the superconductor film having a first region subjected to light illumination, and second and third regions formed contiguously at both sides of the first region such that a width of each of the second and third regions is wider than that of the first region, a bias circuit for supplying a predetermined bias current between the second and third regions, and an output circuit for detecting a change in voltage between the second and third regions, one terminal of said bias circuit and one terminal of said output circuit being commonly grounded, wherein the superconductor film comprises BaPb.sub.1-x Bi.sub.x O.sub.3 (where 0.05.ltoreq.x<0.32) having an I-V characteristic of weak link type under temperature condition less than transition temperature of said BaPb.sub.1-x Bi.sub.x O.sub.3. This simple photodetecting device can detect an optical signal at high speed with high sensitivity.