Decoherence of a particle in a ring

Abstract

We consider a particle coupled to a dissipative environment and derive a perturbative formula for the dephasing rate based on the purity of the reduced probability matrix. We apply this formula to the problem of a particle on a ring, that interacts with a dirty metal environment. At low but finite temperatures we find a dephasing rate $\propto T^{3/2}$, and identify dephasing lengths for large and for small rings. These findings shed light on recent Monte Carlo data regarding the effective mass of the particle. At zero temperature we find that spatial fluctuations suppress the possibility of having a power law decay of coherence.

5 pages, 1 figure, proofed version to be published in EPL

References in corpus (15)

• Intrinsic Decoherence in Mesoscopic Systems
• Impact of the Casimir-Polder Potential and Johnson Noise on Bose-Einstein Condensate Stability near Surfaces
• Interaction effects and phase relaxation in disordered systems
• Thermally induced spin flips above an atom chip
• Quantum Coherence of the Ground State of a Mesoscopic Ring
• Semiclassical theory of shot noise in disordered SN contacts
• Quantum Dissipation versus Classical Dissipation for Generalized Brownian Motion
• Unified Model for The Study of Diffusion Localization and Dissipation
• Dephasing at Low Temperatures
• Comment on "Quantum Decoherence in Disordered Mesoscopic Systems"
• Aharonov-Bohm oscillations of a particle coupled to dissipative environments
• Aharonov-Bohm ring with fluctuating flux
• Interaction-Induced Quantum Dephasing in Mesoscopic Rings
• Interference in presence of Dissipation
• Quantal Brownian Motion - Dephasing and Dissipation

Cited by in corpus (7)

• Particle renormalizations in presence of dissipative environments
• Persistent current noise and electron-electron interactions
• Persistent currents in nanorings and quantum decoherence by Coulomb interaction
• Pure Phase Decoherence in a Ring Geometry
• Renormalization of the dephasing by zero point fluctuations
• The dephasing rate formula in the many body context
• Persistent current noise in normal and superconducting nanorings