@inproceedings{7016e3233122498eb53b86738756e96e,
title = "Onset of superfluidity in 2D optical lattices with bond percolation",
abstract = "The onset of superfluidity in random media has been extensively studied with quantum He4 fluids. The recent observation of superfluid to Mott-insulator quantum phase transition in an ultra cold dilute Bose gas, presents a new prospect for studying such phenomena in a well controlled environment [1]. In particular, by introducing disorder in a controlled manner, new phases of matter are expected to form. Here we focus on the effect of hopping disorder on the onset of superfluidity of a BEC immersed in a deep and disordered optical lattice, where the use of the Bose-Hubbard Hamiltonian is justified. We introduce disorder via a bond percolation model by weakening each nearest-neighbor tunneling element with a probability p. We formulate and solve a renormalization-group equation to find the critical percolation threshold Pc and the accompanying critical exponent v [2]. We check different values for the strength of the weakened bond ranging from the Mott-insulator regime to the superfluid regime and find that there is a critical value under which the superfluid response will greatly diminish (see figure 1). We also analyze a mean field version of the same problem, and an exact ID model and indicate possible experiments that may support our results.",
author = "R. Pugatch and N. Bar-Gill and E. Rowen and N. Katz and N. Davidson",
year = "2005",
doi = "10.1109/CLEOE.2005.1568472",
language = "American English",
isbn = "0780389743",
series = "Conference on Lasers and Electro-Optics Europe - Technical Digest",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
pages = "696",
booktitle = "2005 Conference on Lasers and Electro-Optics Europe",
address = "United States",
note = "2005 Conference on Lasers and Elctro-Optics Europe ; Conference date: 12-06-2005 Through 17-06-2005",
}