On the applicability of bosonization and the Anderson-Yuval methods at the strong-coupling limit of quantum impurity problems

Abstract

The applicability of bosonization and the Anderson-Yuval (AY) approach at strong coupling is investigated by considering two generic impurity models: the multichannel interacting resonant-level and the anisotropic Kondo models. The two methods differ in the renormalization of the conduction-electron density of states (DoS) near the impurity site. Reduction of the DoS, absent in bosonization but accounted for in the AY approach, is shown to be vital in some models yet redundant in others. The criterion being the stability of the strong-coupling fixed point. Renormalization of the DoS is essential for an unstable fixed point, but redundant when a decoupled entity with local dynamics is formed. This rule can be used to boost the accuracy of both methods at strong coupling.

4+ pages, 3 figures

References in corpus (2)

• The numerical renormalization group method for quantum impurity systems
• Theory of a resonant level coupled to several conduction electron channels in equilibrium and out-of-equilibrium

Cited by in corpus (9)

• Crossover from adiabatic to antiadiabatic phonon-assisted tunneling in single-molecule transistors
• Quench dynamics of correlated quantum dots
• The interacting resonant level model in nonequilibrium: finite temperature effects
• From thermal equilibrium to nonequilibrium quench dynamics: A conserving approximation for the interacting resonant level
• Efficient impurity-bath trial states from superposed Slater determinants
• Finite-bias transport through the interacting resonant level model coupled to a phonon mode -- a functional renormalization group study
• Realizing the interacting resonant level model using a quantum dot detector
• Local density of states of the interacting resonant level model at zero temperature
• Kondo frustration via charge fluctuations: a route to Mott localisation