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Quadratic Characteristics of Environment Induced Voltage Shot Noise in Josephson Junctions.

ABSTRACT: We investigate theoretically and experimentally the environment-induced voltage shot noise in current biased Josephson junctions induced by phase particle tunneling. Quantum mechanical treatment based on the Caldeira-Leggett model with tight-binding formulation in local Wannier bases gives a clear picture of the voltage shot noise. A universal form of the zero-frequency noise spectrum is obtained, which exhibits a quadratic dependence on the mean voltage in small bias region. The quadratic dependence is verified experimentally on junctions covering a wide range of parameters, and is found also in junction arrays of various array sizes.

SUBMITTER: Wang JY

PROVIDER: S-EPMC5472641 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Quadratic Characteristics of Environment Induced Voltage Shot Noise in Josephson Junctions.

Wang Jyh-Yang JY Chung Tao-Hsiang TH Lee Teik-Hui TH Chen Chii-Dong CD

Scientific reports 20170615 1

We investigate theoretically and experimentally the environment-induced voltage shot noise in current biased Josephson junctions induced by phase particle tunneling. Quantum mechanical treatment based on the Caldeira-Leggett model with tight-binding formulation in local Wannier bases gives a clear picture of the voltage shot noise. A universal form of the zero-frequency noise spectrum is obtained, which exhibits a quadratic dependence on the mean voltage in small bias region. The quadratic depen ...[more]

PMID: 28620236

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