2012/12/20 by Vipin Kerala Varma, Varma, Vipin Kerala, H. Monien +2
Physics and Astronomy · #Atomic and Subatomic Physics Research #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #Quantum Gases (cond-mat.quant-gas) #Quantum, superfluid, helium dynamics #Strongly Correlated Electrons (cond-mat.str-el) #cond-mat.quant-gas #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.1212.5191
5 pages, 4 figures, 2 column format
arxiv created 2012/12/20 · openalex publication_date 2012/12/20 · arxiv updated 2012/12/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Motivated by excellent comparisons of spin wave theory (SWT) with Quantum Monte Carlo (QMC) calculations of non-interacting hardore bosons (Bernardet et al.) and superlattices (Hen et al.), we develop an SWT for interacting hardcore bosons on a d-dimensional cubic lattice at zero temperature and compare thermodynamical properties with results of Stochastic Series Expansions (SSE): there is good comparison between SWT and SSE results for the simple cubic lattice at small repulsive strengths but differences arise between the results of the two approaches for the square lattice at strong repulsions. The boundaries of the three phases - Mott insulating (MI), superfluid (SF) and Néel solid (NS) - can be readily estimated from calculations of particle density, signalling either a first order (SF <--> NS) or second order transition (MI <--> SF). Comparison is made with results of the Bethe ansatz in one dimension and QMC in two dimensions.