2011/04/26 by Roberta Citro, Adele Naddeo, Edmond Orignac
Physics and Astronomy · #Binary number #Boson #Cold Atom Physics and Bose-Einstein Condensates #Instability #Quantum #Quantum chaos and dynamical systems #Quantum many-body systems #Quantum tunnelling #Realization (probability) #Semiclassical physics #Spin (aerodynamics) #cond-mat.quant-gas #physics.atom-ph
paper · pdf · doi:10.1088/0953-4075/44/11/115306
published as J. Phys. B: At. Mol. Opt. Phys. 44 (2011) 115306 · 12 pages, 7 figures, accepted for publication in J. Phys. B
arxiv created 2011/04/26 · openalex publication_date 2011/05/19 · arxiv updated 2015/05/28 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
Abstract\nWe study the quantum dynamics of a binary mixture of Bose-Einstein condensates (BEC) in a double-well potential starting from a two-mode Bose-Hubbard Hamiltonian. Focussing on the regime where the number of atoms is very large, a mapping onto a SU (2) spin problem together with a Holstein-Primakoff transformation is performed. The quantum evolution of the number difference of bosons between the two wells is investigated for different initial conditions, which range from the case of a small imbalance between the two wells to a coherent spin state. The results show an instability towards a phase-separation above a critical positive value of the interspecies interaction while the system evolves towards a coherent tunneling regime for negative interspecies interactions. A comparison with a semiclassical approach is discussed together with some implications on the experimental realization of phase separation with cold atoms.