Excitation spectrum of a 2D long-range Bose-liquid with a supersymmetry

TL;DR

This paper investigates the excitation spectrum of a 2D long-range Bose-liquid with supersymmetry, revealing a roton-like spectrum and a quantum phase transition between superfluid and crystal phases.

Contribution

It introduces a novel analysis of a specific 2D strongly interacting Bose model using a mapping to classical stochastic dynamics, uncovering new spectral features and phase transition insights.

Findings

Presence of a roton-like spectrum with a very small gap

Identification of a quantum phase transition between superfluid and crystal phases

Broad range of coupling strengths exhibiting these phenomena

Abstract

We have studied excitation spectrum of the specfic 2D model of strongly interacting Bose particles via mapping of the many-body Schrodinger equation in imaginary time to the classical stochastic dynamics. In a broad range of coupling strength $\alpha$ a roton-like spectrum is found, with the roton gap being extremely small in natural units. A single quantum phase transition between strongly correlated supefluid and quantum Berezinsky crystal is found.