https://doi.org/10.1140/epjb/e2005-00114-7
Transitions to the Fulde-Ferrell-Larkin-Ovchinnikov phases at low temperature in two dimensions
Laboratoire de Physique Statistique, École Normale Supérieure (Associated to the CNRS and Paris 6 and Paris 7 Universities) ,
24 rue Lhomond, 75231 Paris Cedex 05, France
Corresponding author: a combesco@lps.ens.fr
Received:
17
November
2004
Revised:
13
January
2005
Published online:
20
April
2005
We explore the nature of the transition to the Fulde-Ferrell-Larkin- Ovchinnikov superfluid phases in the low temperature range in two dimensions, for the simplest isotropic BCS model. This is done by applying the Larkin-Ovchinnikov approach to this second order transition. We show that there is a succession of transitions toward ever more complex order parameters when the temperature goes to zero. This gives rise to a cascade with, in principle, an infinite number of transitions. Except for one case, the order parameter at the transition is a real superposition of cosines with equal weights. The directions of these wavevectors are equally spaced angularly, with a spacing which goes to zero when the temperature goes to zero. This singular behaviour in this T = 0 limit is deeply linked to the two-dimensional nature of the problem.
PACS: 74.20.Fg – BCS theory and its development / 74.60.Ec – Mixed state, critical fields, and surface sheath
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005