Current-phase relationship of granular NbN weak links, inferred from Josephson interferometer characteristics

Journal Article · Sat May 01 00:00:00 EDT 1982 · Appl. Phys. Lett.; (United States)

DOI:https://doi.org/10.1063/1.93248· OSTI ID:5582560

Claassen, J H

Small-area dc superconducting quantum interference devices (SQUID's) were made using ultra-short variable-thickness microbridges of NbN. The bridges had an effective length of approx.500 A and a width of approx.1.5 ..mu..m. Analysis of the response to magnetic flux permits interferences to be drawn about the current-phase relationship (CPR) of the bridges. Contrary to predictions of Ginzburg--Landau theory for microbridges of these dimensions, it is found that the CPR is single valued and probably close to ideal (sinusoidal) over a large temperature range (>2.5 K). The discrepancy with theory may be due to the granular nature of the NbN films.

• Research Organization: Naval Research Laboratory, Washington, D. C. 20375
• OSTI ID: 5582560
• Journal Information: Appl. Phys. Lett.; (United States), Journal Name: Appl. Phys. Lett.; (United States) Vol. 40:9; ISSN APPLA
• Country of Publication: United States
• Language: English

Related Subjects

420201* -- Engineering-- Cryogenic Equipment & Devices
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CURRENTS
DATA
DIMENSIONS
ELECTRIC BRIDGES
ELECTRIC CURRENTS
ELECTRICAL EQUIPMENT
ELECTRONIC EQUIPMENT
EQUIPMENT
EXPERIMENTAL DATA
FILMS
FLUXMETERS
FUNCTIONS
GINZBURG-LANDAU THEORY
INFORMATION
INTERFEROMETERS
JOSEPHSON EFFECT
LENGTH
MAGNETIC FLUX
MEASURING INSTRUMENTS
MICROWAVE EQUIPMENT
NIOBIUM COMPOUNDS
NIOBIUM NITRIDES
NITRIDES
NITROGEN COMPOUNDS
NUMERICAL DATA
PHASE SHIFT
PNICTIDES
RESPONSE FUNCTIONS
SQUID DEVICES
SUPERCONDUCTING DEVICES
THICKNESS
TRANSITION ELEMENT COMPOUNDS
WIDTH