arXiv:cond-mat/9510094 · Physical review. B, Condensed matter
Dynamics of a heavy particle in a Luttinger liquid
A. H. Castro Neto, Matthew P. A. Fisher
Abstract
We study the dynamics of a heavy particle of mass M moving in a one-dimensional repulsively interacting Fermi gas. The Fermi gas is described using the Luttinger model and bosonization. By transforming to a frame comoving with the heavy particle, we map the model onto a generalized ``quantum impurity problem.'' A renormalization-group calculation reveals a crossover from strong to weak coupling upon scaling down in temperature. Above the crossover temperature scale ${\mathit{T}}^{\mathrm{*}}$=(m/M)${\mathit{E}}_{\mathit{F}}$, the particle's mobility \ensuremath{\mu} is found to be (roughly) temperature independent and proportional to the dimensionless conductance g, characterizing the one-dimensional Luttinger liquid. Here m(\ensuremath{\ll}M) is the fermion mass, and ${\mathit{E}}_{\mathit{F}}$ the Fermi energy. Below ${\mathit{T}}^{\mathrm{*}}$, in the weak-coupling regime, the mobility grows and diverges as \ensuremath{\mu}(T)\ensuremath{\sim}${\mathit{T}}^{\mathrm{\ensuremath{-}}4}$ in the T\ensuremath{\rightarrow}0 limit. \textcopyright{} 1996 The American Physical Society.