Equation of state and self-bound droplet in Rabi-coupled Bose mixtures
Authors: Cappellaro A., Macri T., Bertacco GF., Salasnich L.
Autors Affiliation: Univ Padua, Dipartimento Fis Astron Galileo Galilei, Via Marzolo 8, I-35131 Padua, Italy; Univ Fed Rio Grande do Norte, Dept Fis Teor & Expt, BR-59070405 Natal, RN, Brazil; Int Inst Phys, BR-59070405 Natal, RN, Brazil; CNR, INO, Via Nello Carrara 1, BR-50019 Sesto Fiorentino, Brazil
Abstract: Laser induced transitions between internal states of atoms have been playing a fundamental role to manipulate atomic clouds for many decades. In absence of interactions each atom behaves independently and their coherent quantum dynamics is described by the Rabi model. Since the experimental observation of Bose condensation in dilute gases, static and dynamical properties of multicomponent quantum gases have been extensively investigated. Moreover, at very low temperatures quantum fluctuations crucially affect the equation of state of many-body systems. Here we study the effects of quantum fluctuations on a Rabi-coupled two-component Bose gas of interacting alkali atoms. The divergent zero-point energy of gapless and gapped elementary excitations of the uniform system is properly regularized obtaining a meaningful analytical expression for the beyond-mean-field equation of state. In the case of attractive inter-particle interaction we show that the quantum pressure arising from Gaussian fluctuations can prevent the collapse of the mixture with the creation of a self-bound droplet. We characterize the droplet phase and discover an energetic instability above a critical Rabi frequency provoking the evaporation of the droplet. Finally, we suggest an experiment to observe such quantum droplets using Rabi-coupled internal states of K-39 atoms.
Journal/Review: SCIENTIFIC REPORTS
Volume: 7 Pages from: 13358-1 to: 13358-9
KeyWords: INTERFEROMETRY; GASESDOI: 10.1038/s41598-017-13647-yCitations: 40data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2021-10-24References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here