2001/03/01 by J. K. Jung, Seung H Baek, Seung Ho Baek +5 · 1 citation
Materials Science · Physics and Astronomy · #Iron-based superconductors research #Physics of Superconductivity and Magnetism #Superconductivity in MgB2 and Alloys #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.64.012514
arxiv created 2001/03/01 · openalex publication_date 2001/06/15 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
11B NMR and nuclear-spin-lattice relaxation rate (NSLR) are reported at 7.2 T and 1.4 T in powder samples of the intermetallic compound MgB2 with the superconducting transition temperature in zero field Tc=39.2 K. From the first-order quadrupole perturbed NMR spectrum a quadrupole coupling frequency of 835\ifmmode±\else\textpm\fi5 kHz is obtained. The Knight shift is very small and it decreases to zero in the superconducting phase. The NSLR follows a linear law with T1T=165\ifmmode±\else\textpm\fi10 (secK). The results in the normal phase indicate a negligible s character of the wave function of the conduction electrons at the Fermi level. Below Tc the NSLR is strongly field dependent indicating the presence of an important contribution related to the density and the thermal motion of flux lines. No coherence peak is observed at the lower field investigated (1.4 T).