de Haas-van Alphen Study of the Fermi Surfaces of Superconducting LiFeP and LiFeAs

C. Putzke , A. I. Coldea , I. Guillamon , David Vignolles (1) , A. Mccollam , D. Leboeuf (1, 2) , M. D.Watson , I. I. Mazin (3) , S. Kasahara , T. Terashima (4) , T. Shibauchi (5) , Y. Matsuda , A. Carrington

1 LNCMI-T - Laboratoire national des champs magnétiques intenses - Toulouse
2 CEA - Commissariat à l'énergie atomique et aux énergies alternatives
3 NRL - Naval Research Laboratory
4 Research Center for Low Temperature and Materials Sciences
5 Department of Physics, Kyoto University

We report a de Haas-van Alphen oscillation study of the 111 iron pnictide superconductors LiFeAs with T-c approximate to 18 Kand LiFeP with T-c approximate to 5 K. We find that for both compounds the Fermi surface topology is in good agreement with density functional band-structure calculations and has almost nested electron and hole bands. The effective masses generally showsignificant enhancement, up to similar to 3 for LiFeP and similar to 5 for LiFeAs. However, one hole Fermi surface in LiFeP shows a very small enhancement, as compared with its other sheets. This difference probably results from k-dependent coupling to spin fluctuations and may be the origin of the different nodal and nodeless superconducting gap structures in LiFeP and LiFeAs, respectively.

Domaines: Supraconductivité [cond-mat.supr-con]

C. Putzke, A. I. Coldea, I. Guillamon, David Vignolles, A. Mccollam, et al.. de Haas-van Alphen Study of the Fermi Surfaces of Superconducting LiFeP and LiFeAs. Physical Review Letters, 2012, 108, pp.047002. ⟨hal-00687232⟩