# Excitations and stability of weakly interacting Bose gases with multi-body interactions

## TL;DR

This paper analyzes the excitations and stability of weakly interacting Bose gases with multi-body interactions, exploring contact and non-local cases, and applying findings to realistic systems like dipolar and Rydberg-dressed atoms.

## Contribution

It provides a comprehensive analysis of multi-body interactions in Bose gases using Bogoliubov approximation, including contact, non-local, and realistic system applications.

## Key findings

- Quasi-particle spectra and stability criteria derived for multi-body contact interactions.
- Effects of non-local 3-body interactions on Bose gas excitations analyzed.
- Impacts of 3-body terms in dipolar and Rydberg-dressed systems studied.

## Abstract

We consider weakly interacting bosonic gases with local and non-local multi-body interactions. By using the Bogoliubov approximation, we first investigate contact interactions, studying the case in which the interparticle potential can be written as a sum of N-body {\delta}-interactions, and then considering general contact potentials. Results for the quasi-particle spectrum and the stability are presented. We then examine non-local interactions, focusing on two different cases of 3-body non-local interactions. Our results are used for systems with 2- and 3-body {\delta}-interactions and applied for realistic values of the trap parameters. Finally, the effect of conservative 3-body terms in dipolar systems and soft-core potentials (that can be simulated with Rydberg dressed atoms) is also studied.