Quantum electrodynamic fluctuations of the macroscopic Josephson phase
arXiv:cond-mat/0308567 · doi:10.1016/j.aop.2003.08.014
Abstract
We study the equilibrium dynamics of the relative phase in a superconducting Josephson link taking into account the quantum fluctuations of the electromagnetic vacuum. The photons act as a superohmic heat bath on the relative Cooper pair number and thus, indirectly, on the macroscopic phase difference ϕ. This leads to an enhancement of the mean square <ϕ^2> that adds to the spread due to the Coulomb interaction carried by the longitudinal electromagnetic field. We also include the interaction with the electronic degrees of freedom due to quasiparticle tunneling, which couple to the phase and only indirectly to the particle number. The simultaneous inclusion of both the radiation field fluctuations and quasiparticle tunneling leads to a novel type of particle--bath Hamiltonian in which the quantum particle couples through its position and momentum to two independent bosonic heat baths. We study the interplay between the two mechanisms in the present context and find interference contributions to the quantum fluctuations of the phase. We explore the observability of the QED effects discussed here.
19 pages
References in corpus (15)
- Collapse and Revival of the Matter Wave Field of a Bose-Einstein Condensate
- Intrinsic Decoherence in Mesoscopic Systems
- Interaction effects and phase relaxation in disordered systems
- Quantum Decoherence in Disordered Mesoscopic Systems
- Dephasing in Metals by Two-Level Systems in the 2-Channel-Kondo Regime
- Decoherence and Quantum Fluctuations
- Collapses and revivals in the interference between two Bose-Einstein condensates formed in small atomic samples
- Quantum Coherence of the Ground State of a Mesoscopic Ring
- Phase dynamics after connection of two separate Bose-Einstein condensates
- Dephasing at Low Temperatures
- Quantum thermodynamics of systems with anomalous dissipative coupling
- Interactions and Weak Localization: Perturbation Theory and Beyond
- Zero-point fluctuations in the ground state of a mesoscopic normal ring
- Non-linear effects and dephasing in disordered electron systems
- Master Equation for Electromagnetic Dissipation and Decoherence of Density Matrix
Cited by in corpus (9)
- Super-Radiant Dynamics, Doorways, and Resonances in Nuclei and Other Open Mesoscopic Systems
- Entanglement dynamics in chains of qubits with noise and disorder
- Absence of a dissipative quantum phase transition in Josephson junctions
- Momentum coupling in non-Markovian Quantum Brownian motion
- Dissipative quantum oscillator with two competing heat baths
- Quasiclassical frustration
- Minimal coupling in oscillator models of quantum dissipation
- Control of quantum thermodynamic behaviour of a charged magneto oscillator with momentum dissipation
- Absence of a dissipative quantum phase transition in Josephson junctions: Theory