ITA
ENG

Evidence for strong-coupling s-wave superconductivity in MgB2: B-11 NMR study - art. no. 127001

Authors

Kotegawa, H Ishida, K Kitaoka, Y Muranaka, T Akimitsu, J

Citation

H. Kotegawa et al., Evidence for strong-coupling s-wave superconductivity in MgB2: B-11 NMR study - art. no. 127001, PHYS REV L, 8712(12), 2001, pp. 7001

Citations number

Categorie Soggetti

Physics

Journal title

PHYSICAL REVIEW LETTERS

ISSN journal

00319007 → ACNP

Volume

8712

Issue

Year of publication

2001

Database

ISI

SICI code

0031-9007(20010917)8712:12<7001:EFSSSI>2.0.ZU;2-L

Abstract

We have investigated a gap structure in a newly discovered superconductor, MgB2, through measurement of the B-11 nuclear spin-lattice relaxation rate, (11)(1/T-1). (11) (1/T-1) is proportional to the temperature (T) in the no rmal state, and decreases exponentially in the superconducting (SC) state, revealing a tiny coherence peak just below T-c. The T dependence of 1/T-1 i n the SC state can be accounted for by an s-wave SC model with a large gap size of 2 Delta /k(B)T(c) similar to 5 which suggests it is in a strong-cou pling regime.