arXiv:cond-mat/0410446 · Physical Review B
Unification of electromagnetic noise and Luttinger liquid via a quantum dot
Karyn Le Hur, Mei-Rong Li
Abstract
We investigate the effect of dissipation on a small quantum dot (resonant level) tunnel coupled to a chiral Luttinger liquid (LL) with the LL parameter $K$. The dissipation stems from the coupling of the dot to an electric environment, being characterized by the resistance $R$, via Coulomb interactions. We show that this problem can be mapped onto a Caldeira-Leggett model where the (ohmic) bath of harmonic oscillators is governed by the effective dissipation strength $\ensuremath{\alpha}={(2\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{K})}^{\ensuremath{-}1}$ with ${\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{K}}^{\ensuremath{-}1}={K}^{\ensuremath{-}1}+2R∕{R}_{K}$ and ${R}_{K}=h∕{e}^{2}$ the quantum of resistance. Experimental consequences are discussed and the limit $K=1∕{2}^{+}$ is thoroughly studied at small $R∕{R}_{K}$ through the spin-boson-fermion model.