The light-cone spreading of entanglement and correlation is a fundamental and ubiquitous feature of homogeneous extended quantum systems. Here we point out that a class of inhomogenous Luttinger liquids (those with a uniform Luttinger parameter K) at low energy display the universal phenomenon of curved light cones: gapless excitations propagate along the null geodesics of the metric ds(2) = d x(2) - v (x)(2)d t(2), with v (x) being the calculable spatial dependent velocity induced by the inhomogeneity. We confirm our findings with explicit analytic and numerical calculations both in-and out-of-equilibrium for a Tonks-Girardeau gas in a harmonic potential and in lattice systems with artificially tuned hamiltonian density.
|Titolo:||Emergence of curved light-cones in a class of inhomogeneous Luttinger liquids|
|Autori:||Dubail, Jerome; Stephan, Jean-marie; Calabrese, Pasquale|
|Data di pubblicazione:||2017|
|Digital Object Identifier (DOI):||10.21468/SciPostPhys.3.3.019|
|Fulltext via DOI:||10.21468/SciPostPhys.3.3.019|
|Appare nelle tipologie:||1.1 Journal article|