Microwave coupling of frequency-locked Josephson junction arrays

Journal Article · Sun Jun 01 04:00:00 EDT 1997 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.118430· OSTI ID:529986

Song, I; Eom, Y; Park, G ^[1]; Lee, E; Park, S ^[2]

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1. Department of Physics, Sogang University, Seoul 100-611 (Korea)
2. Electronic Materials Laboratory, Samsung Advanced Institute of Technology, Suwon (Korea)

A high temperature superconducting YBa{sub 2}Cu{sub 3}O{sub y} array of five Josephson junctions designed with additional coupling lines has been developed to demonstrate the effects of frequency locking and impedance matching for applications such as oscillators, mixers, and detectors. The Josephson self-radiation power was directly detected by a superheterodyne receiver, and Shapiro steps were also measured. The Josephson self-radiation properties reveal good quality of phase locking and microwave coupling with external circuits. The maximum self-radiation power of our array is about 50 pW which is several ten times higher than that of a single Josephson junction, and its peak point exactly satisfies the Josephson current-voltage relation. The Shapiro-step measurements show that the behavior of current-voltage curve depends on the effective inductance of coupling lines which affects the total impedance of Josephson junction array and microwave coupling. The Josephson oscillation frequency was obtained up to about 880 GHz which is 73{percent} of the maximum available frequency calculated from the characteristic voltage of the Josephson junctions. Experimental results show that this type of Josephson junction array can improve the Josephson self-radiation power and increase the maximum detectable frequency. {copyright} {ital 1997 American Institute of Physics.}

• OSTI ID: 529986
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 24 Vol. 70; ISSN 0003-6951; ISSN APPLAB
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BARIUM COMPOUNDS
BARIUM OXIDES
COPPER OXIDES
GHZ RANGE
HIGH-TC SUPERCONDUCTORS
JOSEPHSON JUNCTIONS
MICROELECTRONICS
MICROWAVE RADIATION
OSCILLATORS
TUNING
YTTRIUM COMPOUNDS
YTTRIUM OXIDES