Realization of an Excited, Strongly-Correlated Quantum Gas Phase

TL;DR

This paper reports the experimental realization of a highly excited, strongly correlated quantum gas phase in one dimension, stabilized by quantum correlations across a confinement-induced resonance, enabling study of metastable excited many-body states.

Contribution

It demonstrates the creation and control of an excited, strongly correlated quantum phase in a tunable one-dimensional bosonic gas, which was previously inaccessible.

Findings

Observation of the crossover from repulsive to attractive interactions.

Stability of the excited phase due to quantum correlations.

Potential to explore dynamical properties of metastable states.

Abstract

Ultracold atomic physics offers myriad possibilities to study strongly correlated many-body systems in lower dimensions. Typically, only ground state phases are accessible. Using a tunable quantum gas of bosonic cesium atoms, we realize and control in one dimensional geometry a highly excited quantum phase that is stabilized in the presence of attractive interactions by maintaining and strengthening quantum correlations across a confinement-induced resonance. We diagnose the crossover from repulsive to attractive interactions in terms of the stiffness and the energy of the system. Our results open up the experimental study of metastable excited many-body phases with strong correlations and their dynamical properties.