Volume 79, Number 6, September 2007
Article Number 67001
Number of page(s) 6
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
Published online 07 August 2007
EPL, 79 (2007) 67001
DOI: 10.1209/0295-5075/79/67001

Anomalous fluctuation regimes at FFLO transition

F. Konschelle1, J. Cayssol1 and A. I. Buzdin1, 2

1  Universités de Bordeaux, CPMOH, CNRS - 33405, Talence Cedex, France
2  Institut Universitaire de France - 75005, Paris, France

received 19 June 2007; accepted in final form 23 July 2007; published September 2007
published online 7 August 2007

Recently some experimental evidences have been obtained in favour of the existence of the inhomogeneous Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superconducting state. However the unambiguous identification of FFLO state remains very difficult. Since the region of the critical fluctuations is extremely narrow in superconductors, we investigate theoretically the Gaussian fluctuations near the FFLO transition and demonstrate that the behaviors of the fluctuational specific heat and paraconductivity in the normal state are qualitatively different from the usual superconducting transition. Special values of the critical exponents and the crossovers between different fluctuational regimes may provide a unique test for the FFLO state appearance.

74.81.-g - Inhomogeneous superconductors and superconducting systems.
74.40.+k - Fluctuations (noise, chaos, nonequilibrium superconductivity, localization, etc.).
03.75.Mn - Multicomponent condensates; spinor condensates.

© Europhysics Letters Association 2007