A bosonic gas formed by two interacting species trapped in a double-well potential features macroscopic localization effects when the interspecies interaction becomes sufficiently strong. A repulsive interaction spatially separates the species into different wells while an attractive interaction confines both species in the same well. We perform a fully analytic study of the transitions from the weak- to the strong-interaction regime by exploiting the semiclassical method in which boson populations are represented in terms of continuous variables. We find an explicit description of low-energy eigenstates and spectrum in terms of the model parameters which includes the neighborhood of the transition point. To test the effectiveness of the continuous-variable method we compare its predictions with the exact results found numerically. Numerical calculations confirm the spectral collapse evidenced by this method when the space localization takes place.
Continuous-variable approach to the spectral properties and quantum states of the two-component Bose-Hubbard dimer / Lingua, Fabio; Penna, Vittorio. - In: PHYSICAL REVIEW. E. - ISSN 2470-0045. - STAMPA. - 95(2017). [10.1103/PhysRevE.95.062142]
|Titolo:||Continuous-variable approach to the spectral properties and quantum states of the two-component Bose-Hubbard dimer|
|Data di pubblicazione:||2017|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1103/PhysRevE.95.062142|
|Appare nelle tipologie:||1.1 Articolo in rivista|