Investigation of Quantum Droplet: An Analytical Approach

TL;DR

This paper analytically investigates the formation and stability of quantum droplets in quasi-one-dimensional Bose-Einstein condensates, highlighting the balance of interactions and providing solutions to the modified Gross-Pitaevskii equation.

Contribution

It introduces two analytical solutions to the cubic-quartic nonlinear Schrödinger equation for droplet formation and analyzes their stability in a quasi-one-dimensional setting.

Findings

Analytical solutions to the CQNLSE were derived and verified numerically.

Parameter regimes for stable droplet formation were identified.

Regions of soliton dominance and self-bound droplets were mapped.

Abstract

Recent observations of droplets in dipolar and binary Bose-Einstein condensate (BEC) motivates us to study the theory of droplet formation in detail. Precisely, we are interested in investigating the possibility of droplet formation in a quasi-one-dimensional geometry. The recent observations have concluded that the droplets are stabilized by the competition between effective mean-field and beyond mean-field interaction. Hence, it is possible to map the effective equation of motion to a cubic-quartic nonlinear Schr\"odinger equation (CQNLSE). We obtain two analytical solutions of the modified Gross-Pitaevskii equation or CQNLSE and verified them numerically. Based on their stability we investigate the parameter regime for which droplets can form. The effective potential allows us to conclude about the regions of soliton domination and self-bound droplet formations.