Polarized Rabi-Coupled and Spinor Boson Droplets

TL;DR

This paper theoretically investigates the stability of quantum droplets in polarized Rabi-coupled Bose mixtures and spinor gases, analyzing how polarization and external parameters influence their phase diagrams and stability.

Contribution

It extends previous studies by exploring the effects of polarization on droplet stability and provides phase diagrams for polarized Rabi-coupled and spinor Bose gases.

Findings

Calculated Lee-Huang-Yang corrections for polarized systems.

Mapped phase diagrams of droplet stability in parameter space.

Identified similarities and differences between the two systems.

Abstract

Self-bound quantum droplets form when the mean-field tendency of the gas to collapse is stabilized by the effectively repulsive beyond mean-field fluctuations. The beyond mean-field effects depend on Rabi-frequency $\omega_R$ and quadratic Zeeman effect $q$ for the Rabi-coupled Bose mixtures and the spinor gases, respectively. The effects of varying $\omega_R$ and $q$ on the quantum droplet have recently been examined for unpolarized Rabi-coupled Bose mixture with zero detuning $\delta = 0$ and unpolarized spinor gas with $\langle F_z \rangle=0$. In this paper, we theoretically explore the stability of the droplet phase for polarized $\delta \neq 0$ Rabi-coupled Bose mixture and $\langle F_z \rangle \neq 0$ spinor gas. We calculate the Lee-Huang-Yang corrections for both gases with polarized order parameters and obtain the phase diagram of the droplets on the parameter space of $\omega_R$-$\delta$ and $q$-$p$ for Rabi-coupled mixture and spinor gas, respectively. Finally, we highlight the similarities and differences between the two systems and discuss their experimental feasibility.