Possible Fulde-Ferrell-Larkin-Ovchinnikov Superconducting State in CeCoIn5
Abstract
We report specific heat measurements of the heavy fermion superconductor CeCoIn5 in the vicinity of the superconducting critical field Hc2, with magnetic fields in the [110], [100], and [001] directions, and at temperatures down to 50mK. The superconducting phase transition changes from second to first order for fields above 10T for H∥[110] and H∥[100]. In the same range of magnetic fields, we observe a second specific heat anomaly within the superconducting state. We interpret this anomaly as a signature of a Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) inhomogeneous superconducting state. We obtain similar results for H∥[001], with the FFLO state occupying a smaller part of the phase diagram.
- Publication:
-
Physical Review Letters
- Pub Date:
- October 2003
- DOI:
- arXiv:
- arXiv:cond-mat/0304420
- Bibcode:
- 2003PhRvL..91r7004B
- Keywords:
-
- 74.70.Tx;
- 71.27.+a;
- 74.25.Fy;
- 75.40.Cx;
- Heavy-fermion superconductors;
- Strongly correlated electron systems;
- heavy fermions;
- Transport properties;
- Static properties;
- Condensed Matter - Strongly Correlated Electrons
- E-Print:
- 4 pages, 3 figures, submitted to Phys. Rev. Letters