SciPost logo

The complete scientific publication portal
Managed by professional scientists
For open, global and perpetual access to science

Emergence of curved light-cones in a class of inhomogeneous Luttinger liquids

Jérôme Dubail, Jean-Marie Stéphan, Pasquale Calabrese

SciPost Phys. 3, 019 (2017) · published 6 September 2017


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 geodesics of the metric $ds^2=dx^2+v(x)^2 d\tau^2$, 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.

View more material from these authors:

Dubail, Jerome  ·  Calabrese, Pasquale  ·  Stéphan, Jean-Marie