Quasistates in a ring coupled to a reservoir and their relation to the Dicke effect

Abstract

We study the energy spectrum and the persistent current in an ideal one-dimensional mesoscopic ring coupled to an external fermionic reservoir. The contact between ring and reservoir is described by a tunneling operator, which causes an indirect coupling between different ring states via states in the reservoir. For strong coupling to the reservoir new quasistates with sharp eigenenergies develop inside the ring. The formation of long-living states at strong tunnel coupling to the reservoir is analogous to the Dicke effect in optics, that was recently investigated in context of resonant scattering and resonant tunneling in solid state systems. Our model reproduces the results obtained in previous work based on the scattering matrix approach and furthermore it describes a new stable energy spectrum in the limit of strong coupling.

10 pages, 12 figures

References in corpus (4)

• Energy spectra of quantum rings
• Flux-Dependent Level Attraction in Double-Dot Aharonov-Bohm Interferometers
• Aharonov-Bohm interferometry with quantum dots: scattering approach versus tunneling picture
• Kondo effect in a two-level quantum dot coupled to an external fermionic reservoir

Cited by in corpus (8)

• Interference traps waves in open system: Bound states in the continuum
• Superradiance Transition in Transport Through Nanosystems
• Controlling Fano and Dicke effects via a magnetic flux in a double quantum-dot molecule
• Bound states in the continuum in open Aharonov-Bohm rings
• Kondo-Dicke resonances in electronic transport through triple quantum dots
• Persistent current magnification in a double quantum-ring system
• The role of the indirect tunneling processes and asymmetry in couplings in orbital Kondo transport through double quantum dots
• Interplay between electron pairing and Dicke effect in triple quantum dots structures