
ON THERMAL FLUCTUATIONS IN A JOSEPHSON-FLUXON OSCILLATOR
Author(s) -
Qiang-Hua Wang,
X.X. Yao
Publication year - 1993
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.42.1661
Subject(s) - fluxon , physics , adiabatic process , josephson effect , adiabatic theorem , quantum mechanics , quantum electrodynamics , thermal fluctuations , perturbation theory (quantum mechanics) , scattering , pi josephson junction , superconductivity
Thermal fluctuations in a Josephson-fluxon oscillator are considered with emphasises on the stochastic dynamics of fluxon and the non-trivial continuum-mode excitations. Analytical expressions for the radiation line-width of the oscillator are derived from perturbation theory and standard stochastic process theory. The averaged kinetic energy of a low-velocity fluxon is shown to be kBT/2. The continuum excitations are explored in the framework of the inverse scattering transform approach. The averaged energy per wave mode turns out to be kBT,and this justifies the adiabatic approximation applied in the fluxon stochastic dynamics.