Finite-interaction effects on correlation enhancement

Determine quantitatively how the dynamical suppression of thermal effects in density-density correlations after a trap quench is modified away from the Tonks–Girardeau limit by quasiparticle dressing, including its effects on both the hydrodynamic background and the effective theory of fluctuations.

Background

The paper develops a finite-temperature Quantum Generalized Hydrodynamics description of density-density correlations following trap quenches in the Tonks–Girardeau limit of the Lieb–Liniger gas. In this limit, the model maps to free fermions, allowing the authors to exploit conformal invariance and obtain closed analytical expressions.

The authors expect the observed dynamical suppression of thermal contributions, and the resulting approach of bulk correlations toward the zero-temperature equilibrium form, to persist at finite interaction because of the universal character of Tomonaga–Luttinger theory. However, finite interactions introduce quasiparticle dressing, which changes both the evolving hydrodynamic background and the effective fluctuation theory. The quantitative impact of this dressing on correlation enhancement is therefore left unresolved.