title: Critical exponents of the superfluid-Bose-glass transition in three dimensions.
abstract: Recent experimental and numerical studies of the critical-temperature exponent ϕ for the superfluid-Bose-glass universality in three-dimensional systems report strong violations of the key quantum critical relation, ϕ=νz, where z and ν are the dynamic and correlation-length exponents, respectively; these studies question the conventional scaling laws for this quantum critical point. Using Monte Carlo simulations of the disordered Bose-Hubbard model, we demonstrate that previous work on the superfluid-to-normal-fluid transition-temperature dependence on the chemical potential (or the magnetic field, in spin systems), T_{c}∝(μ-μ_{c})^{ϕ}, was misinterpreting transient behavior on approach to the fluctuation region with the genuine critical law. When the model parameters are modified to have a broad quantum critical region, simulations of both quantum and classical models reveal that the ϕ=νz law [with ϕ=2.7(2), z=3, and ν=0.88(5)] holds true, resolving the ϕ-exponent "crisis."
authors.affiliation: Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA.
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Yao
authors.affiliation: Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA and Instituto de Física, Universidade de São Paulo, 05508-090 São Paulo, Brazil.
authors.forename: Karine P C
authors.initials: KP
authors.lastname: da Costa
authors.affiliation: The Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, I-34151 Trieste, Italy.
authors.forename: Mikhail
authors.initials: M
authors.lastname: Kiselev
authors.affiliation: Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA and Russian Research Center "Kurchatov Institute," 123182 Moscow, Russia.
authors.forename: Nikolay
authors.initials: N
authors.lastname: Prokof'ev