Autor: J.M. Lumley, D. Glowacka, R. Hart, V. Polushkin
Rok vydání: 2000
Předmět:
Zdroj: Journal of Low Temperature Physics. 118:105-111
ISSN: 0022-2291
DOI: 10.1023/a:1004682604553
Popis: This paper presents experimental data on a comparative study of a dc SQUID with voltage and current bias. We introduce a cross-correlated dynamic resistance of the device defined as a ratio R dCV = ηVC/ηIV, where ηVC = (∂V/∂Φ)∣ A is the slope of the voltage-to-flux characteristics measured in the current bias mode and η IV = (∂I/∂Φ)∣ A is the slope of the current-to-flux characteristics measured with voltage bias. It has been found that R dCV may deviate strongly from the dynamic resistance observed in the current bias mode of operation. The intrinsic energy resolution of the SQUID e remains unchanged for both modes of operation, but the current noise of the voltage biased device scales with the cross-correlated dynamic resistance. In our SQUID with the loop inductance L = 105 pH, e is equal to 37 h in the white noise region at a temperature of 4.2 K.
Databáze: OpenAIRE
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