arXiv:1404.0178 · Physical Review B
Relaxation in Luttinger liquids: Bose-Fermi duality
Ivan V. Protopopov, Dmitri B. Gutman, A. D. Mirlin
Abstract
We explore the lifetime of excitations in a dispersive Luttinger liquid. We perform a bosonization supplemented by a sequence of unitary transformations that allows us to treat the problem in terms of weakly interacting quasiparticles. The relaxation described by the resulting Hamiltonian is analyzed by bosonic and (after a refermionization) by fermionic perturbation theory. We show that the fermionic and bosonic formulations of the problem exhibit a remarkable strong-weak coupling duality. Specifically, the fermionic theory is characterized by a dimensionless coupling constant $\ensuremath{\lambda}={m}^{*}{l}^{2}T$ and the bosonic theory by ${\ensuremath{\lambda}}^{\ensuremath{-}1}$, where $1/{m}^{*}$ and $l$ characterize the curvature of the fermionic and bosonic spectra, respectively, and $T$ is the temperature.