RF SQUID based devices for MQC

We present the experimental observation of the effects of macroscopic quantum tunnelling in a SQUID device, consisting of a rf SQUID coupled to a readout system based on a dc SQUID sensor. Data on the decay rate from the metastable flux states of a rf SQUID are reported, both in the classical and quantum regimes. The low dissipation level and the good insulation of the probe from external noise are encouraging in view of building a macroscopic quantum coherent system.

Superconductor Science and TechnologyApr 15, 20049 citations

Measurement of the effective dissipation in an rf SQUID system

B. Ruggiero, Valentina Corato, C. Granata +3 more

Physical review. B, Condensed matterApr 14, 200317 citations

RF SQUID based devices for MQC

Longobardi L., CORATO V., Carmine Granata, ROMBETTO S., M. I. RUSSO, B. Ruggiero, P. Silvestrini

Published Jan 1, 2003• 0 citations

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RF SQUID BASED DEVICES FOR MQC

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The growing amount of theoretical interest in the area of quantum computing have stimulated in recent years research with the aim of developing a corresponding technology. Superconducting Josephson systems appear to be among the most promising candidates. We present the characterization of a fully integrated Josephson device consisting of an RF SQUID coupled to a readout system based on a dc SQUID sensor. We report measurements of the dc SQUID performances showing a high intrinsic responsivity and a low flux noise, giving a good signal to noise ratio in the small signal mode. In the classical regime data on the decay rate from the metastable flux states of RF SQUID are also reported. The low dissipation level and the good insulation of the probe from the external noise are encouraging in view of macroscopic quantum experiments. Work is in progress to improve the design of the device to increase its application capability toward the quantum regime.The growing amount of theoretical interest in the area of quantum computing have stimulated in recent years research with the aim of developing a corresponding technology. Superconducting Josephson systems appear to be among the most promising candidates. We present the characterization of a fully integrated Josephson device consisting of an RF SQUID coupled to a readout system based on a dc SQUID sensor. We report measurements of the dc SQUID performances showing a high intrinsic responsivity and a low flux noise, giving a good signal to noise ratio in the small signal mode. In the classical regime data on the decay rate from the metastable flux states of RF SQUID are also reported. The low dissipation level and the good insulation of the probe from the external noise are encouraging in view of macroscopic quantum experiments. Work is in progress to improve the design of the device to increase its application capability toward the quantum regime.

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We present the characterization of a fully integrated Josephson device consisting of a rf-superconducting quantum interference device (SQUID) coupled to a readout system based on a dc SQUID sensor. Particular care in the design is devoted to minimize the electromagnetic noise coming from the environment. We report data on dc SQUID performances as well as on the decay rate from metastable flux states of the rf SQUID in the classical regime. The low dissipation level and the good insulation of the probe from the external noise are encouraging in view of macroscopic quantum experiments.We present the characterization of a fully integrated Josephson device consisting of a rf-superconducting quantum interference device (SQUID) coupled to a readout system based on a dc SQUID sensor. Particular care in the design is devoted to minimize the electromagnetic noise coming from the environment. We report data on dc SQUID performances as well as on the decay rate from metastable flux states of the rf SQUID in the classical regime. The low dissipation level and the good insulation of the probe from the external noise are encouraging in view of macroscopic quantum experiments.

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We present an experimental study of the effective dissipation of a fully integrated ${\mathrm{N}\mathrm{b}/\mathrm{A}\mathrm{l}\mathrm{O}}_{x}/\mathrm{Nb}$ Josephson device consisting of a rf superconducting quantum interference device (SQUID) coupled to a readout system based on a dc SQUID sensor. In the classical regime data on the decay rate from the metastable flux states of rf SQUID are reported. The low dissipation level and the good insulation of the probe from the external noise are encouraging in view of building a macroscopic quantum device.We present an experimental study of the effective dissipation of a fully integrated ${\mathrm{N}\mathrm{b}/\mathrm{A}\mathrm{l}\mathrm{O}}_{x}/\mathrm{Nb}$ Josephson device consisting of a rf superconducting quantum interference device (SQUID) coupled to a readout system based on a dc SQUID sensor. In the classical regime data on the decay rate from the metastable flux states of rf SQUID are reported. The low dissipation level and the good insulation of the probe from the external noise are encouraging in view of building a macroscopic quantum device.

Physical review. B, Condensed matterApr 14, 200317 citations

We present an experimental study of the effective dissipation of a fully integrated

{\mathrm{N}\mathrm{b}/\mathrm{A}\mathrm{l}\mathrm{O}}_{x}/\mathrm{Nb}

Josephson device consisting of a rf superconducting quantum interference device (SQUID) coupled to a readout system based on a dc SQUID sensor. In the classical regime data on the decay rate from the metastable flux states of rf SQUID are reported. The low dissipation level and the good insulation of the probe from the external noise are encouraging in view of building a macroscopic quantum device.