Volume 108, Number 3, November 2014
|Number of page(s)||6|
|Published online||06 November 2014|
Replica symmetry breaking in the Bose glass
1 SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh - St Andrews, KY16 9SS, UK
2 ISIS Facility, Rutherford Appleton Laboratory - Chilton, Didcot, Oxfordshire OX11 0QX, UK
3 London Centre for Nanotechnology, University College London - Gordon St., London, WC1H 0AH, UK
Received: 4 April 2014
Accepted: 17 October 2014
We investigate the nature of the Bose glass phase of the disordered Bose-Hubbard model in d > 2 and demonstrate the existence of a glass-like replica symmetry breaking (RSB) order parameter in terms of particle number fluctuations. Starting from a strong-coupling expansion around the atomic limit, we study the instability of the Mott insulator towards the formation of a Bose glass. We add some infinitesimal RSB, following the Parisi hierarchical approach in the most general form, and observe its flow under the momentum-shell renormalization group scheme. We find a new fixed point with one-step RSB, corresponding to the transition between the Mott insulator and a Bose glass phase with hitherto unseen RSB. The susceptibility associated to infinitesimal RSB perturbation in the Mott insulator is found to diverge at the transition with an exponent . Our findings are consistent with the expectation of glassy behavior and the established breakdown of self-averaging. We discuss the possibility of measuring the glass-like order parameter in optical-lattice experiments as well as in certain spin systems that are in the same universality class as the Bose-Hubbard model.
PACS: 05.30.Jp – Boson systems / 64.70.P- – Glass transitions of specific systems / 64.60.ae – Renormalization-group theory
© EPLA, 2014
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.