NMR Study of 77Se in Layered Superconducting 2H–NbSe2

摘要: The nuclear spin-lattice relaxation time T 1 and the Knight shift K of 77 Se in 2H–NbSe 2 , an anisotropic type II superconductor, have been measured at 8 MHz low temperatures (1.3–11 K). In normal state, \(^{77}(K){\cong}0.26\)(%) \(^{77}(T_{1}T){\cong}2.0\) secK were obtained. They are independent temperature. superconducting mixed ( ) reduces with decreasing temperature tends to a considerably small but non-zero value ≪ C . corresponding BCS singlet spin pairing. residual is explained by existence spin-orbit interaction. ), increases exponentially energy gap 3.5 k B From data for root mean square anisotropy estimated be order 20% gap. Origins also discussed on basis band structure.