Superfluid density in a two-dimensional model of supersolid
Sepulveda
N
author
Josserand
C
author
Rica
S
author
2010
We study in 2-dimensions the superfluid density of periodically modulated states in the framework of the mean-field Gross-Pitaevskii model of a quantum solid. We obtain a full agreement for the superfluid fraction between a semi-theoretical approach and direct numerical simulations. As in 1-dimension, the superfluid density decreases exponentially with the amplitude of the particle interaction. We discuss the case when defects are present in this modulated structure. In the case of isolated defects (e.g. dislocations) the superfluid density only shows small changes. Finally, we report an increase of the superfluid fraction up to 50% in the case of extended macroscopical defects. We show also that this excess of superfluid fraction depends on the length of the complex network of grain boundaries in the system.
WOS:000286669400004
exported from refbase (show.php?record=121), last updated on Tue, 16 Oct 2012 08:06:33 -0300
text
files/113_Sepulveda_etal2010.pdf
10.1140/epjb/e2010-10176-y
Sepulveda_etal2010
European Physical Journal B
Eur. Phys. J. B
2010
continuing
periodical
academic journal
78
4
439
447
1434-6028