Nature of Intermediate States between Superfluid and Mott insulator for Interacting Bosons in One-dimension with a Harmonic Trapping Potential

TL;DR

This paper investigates the complex quantum phase transitions between superfluid and Mott insulator states in one-dimensional interacting bosons under a harmonic trap, revealing novel many-body effects and intermediate states.

Contribution

It identifies and characterizes successive quantum transitions and intermediate states caused by trap and interaction interplay, highlighting new many-body phenomena.

Findings

Existence of multiple quantum transitions between superfluid and Mott states.

Observation of unconventional long-range correlations.

Detection of an even-odd squeezing process of bosons.

Abstract

Successive quantum transitions in an intermediate regime are shown to exist between the superfluid and Mott insulating states for interacting bosonic atoms in one dimension with a trapping potential. These transitions, which are caused by the interplay of the trapping potential with the competition between the kinetic energy and the interaction, reveal novel many-body effects as reflected by low-lying excitation behavior, unconventional long-range correlations and an even-odd alternating squeezing process of superfluid bosons into the Mott insulating state. These features, most likely being generic for all dimensions when a trapping potential is involved, are relevant for both experimental observations and physical interpretation of the Mott insulator transition.