High-field pauli-limiting behavior and strongly enhanced upper critical magnetic fields near the transition temperature of an arsenic-deficient LaO0.9F0.1FeAs1-delta superconductor

G Fuchs; S-L Drechsler; N Kozlova; G Behr; A Köhler; J Werner; K Nenkov; R Klingeler; J Hamann-Borrero; C Hess; A Kondrat; M Grobosch; A Narduzzo; M Knupfer; J Freudenberger; B Büchner; L Schultz

doi:10.1103/PhysRevLett.101.237003

High-field pauli-limiting behavior and strongly enhanced upper critical magnetic fields near the transition temperature of an arsenic-deficient LaO0.9F0.1FeAs1-delta superconductor

Phys Rev Lett. 2008 Dec 5;101(23):237003. doi: 10.1103/PhysRevLett.101.237003. Epub 2008 Dec 4.

Authors

G Fuchs¹, S-L Drechsler, N Kozlova, G Behr, A Köhler, J Werner, K Nenkov, R Klingeler, J Hamann-Borrero, C Hess, A Kondrat, M Grobosch, A Narduzzo, M Knupfer, J Freudenberger, B Büchner, L Schultz

Affiliation

¹ IFW Dresden, P.O. Box 270116, D-01171 Dresden, Germany.

PMID: 19113583
DOI: 10.1103/PhysRevLett.101.237003

Abstract

We report upper critical field Bc2(T) data for disordered (arsenic-deficient) LaO0.9F0.1FeAs1-delta in a wide temperature and magnetic field range up to 47 T. Because of the large linear slope of Bc2 approximately -5.4 to -6.6 T/K near Tc approximately 28.5 K, the T dependence of the in-plane Bc2(T) shows a flattening near 23 K above 30 T which points to Pauli-limited behavior with Bc2(0) approximately 63-68 T. Our results are discussed in terms of disorder effects within [corrected] unconventional superconducting pairings.