Properties of the Superfluid in the Disordered Bose-Hubbard Model

Autor:	de Abreu, Bruno R., Ray, Ushnish, Vitiello, Silvio A., Ceperley, David M.
Rok vydání:	2018
Předmět:	Condensed Matter - Quantum Gases Condensed Matter - Disordered Systems and Neural Networks Physics - Atomic Physics Quantum Physics
Zdroj:	Phys. Rev. A 98, 023628 (2018)
Druh dokumentu:	Working Paper
DOI:	10.1103/PhysRevA.98.023628
Popis:	We investigate the properties of the superfluid phase in the three-dimensional disordered Bose-Hubbard model using Quantum Monte-Carlo simulations. The phase diagram is generated using Gaussian disorder on the on-site potential. Comparisons with box and speckle disorder show qualitative similarities leading to the re-entrant behavior of the superfluid. Quantitative differences that arise are controlled by the specific shape of the disorder. Statistics pertaining to disorder distributions are studied for a range of interaction strengths and system sizes, where strong finite-size effects are observed. Despite this, both the superfluid fraction and compressibility remain self-averaging throughout the superfluid phase. Close to the superfluid-Bose-glass phase boundary, finite-size effects dominate but still suggest that self-averaging holds. Our results are pertinent to experiments with ultracold atomic gases where a systematic disorder averaging procedure is typically not possible. Comment: 10 pages, 7 figures
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1804.05789 Zobrazit plný text záznamu View this record from Arxiv