A Superconducting Resonator with a Hafnium Microbridge at Temperatures of 50–350 mK

Journal Article · Sun Jul 15 04:00:00 EDT 2018 · Technical Physics Letters

DOI:https://doi.org/10.1134/S106378501807012X· OSTI ID:22786369

Merenkov, A. V.; Chichkov, V. I. ^[1]; Ermakov, A. B. ^[2]; Kim, T. M.; Ustinov, A. V. ^[1]

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1. National University of Science and Technology MISiS (Russian Federation)
2. Russian Academy of Sciences, V.A.Kotel’nikov Institute of Radio Engineering and Electronics (Russian Federation)

A high-quality superconducting resonator with a microbridge of hafnium film for use in a circuit for readout a terahertz-band imaging array with frequency division multiplexing is demonstrated experimentally. The variability of the impedance of the bridge at a frequency of 1.5 GHz, which is a key factor in the control of the quality of the resonator, is studied. The bridge, having a thickness of about 50 nm, a critical temperature T{sub C} ≈ 380 mK, and a plan size of 2.5 × 2.5 μm, was connected as a load of a resonator made of niobium film with a thickness of about 100 nm (T{sub C} ~ 9 K). It is shown that the bridge smoothly changes its impedance proportionally to the bias power in the entire temperature range. The effective thermal insulation of the bridge was measured in a dilution cryostat at temperatures of 50–300 mK. Thermal conductivity G of the bridge was calculated and found to be ~4 × 10{sup –13} W/K, which gives an estimate of the sensitivity of the structure in the bolometric mode NEP ≈ 8 × 10{sup –19} W/Hz{sup 1/2} at a temperature of 150 mK.

• OSTI ID: 22786369
• Journal Information: Technical Physics Letters, Journal Name: Technical Physics Letters Journal Issue: 7 Vol. 44; ISSN 1063-7850
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BOLOMETERS
CRYOSTATS
DILUTION
GHZ RANGE 01-100
HAFNIUM
IMPEDANCE
NIOBIUM
RESONATORS
SUPERCONDUCTING FILMS
SUPERCONDUCTIVITY
THERMAL CONDUCTIVITY
THERMAL INSULATION
THICKNESS
THZ RANGE