抄録
The nuclear spin-lattice relaxation times T1’s and the Knight shift of 93Nb in 2H–NbSe2 in a single crystal and powdered samples have been measured at 10 MHz and at low temperatures. The Knight shift contains both isotropic and anisotropic terms. The isotropic Knight shift, Kiso=−0.03(%), is decomposed into the core-polarization part, Kd=−0.66(%), and the orbital part, Korb=+0.63(%). In normal state, T1 obeys a relation, T1T=65±10 msecK and shows no strong anisotropy. The dependence of T1 on the symmetry properties of the conduction wave functions is discussed. It is concluded that the admixture of d3z2−r2 orbit dominates at the Fermi level and T1 of 93Nb is dominated by the core-polarization interaction. In the superconducting state T1 varies exponentially as in the case of bulk BCS superconductor with energy gap of 3.5 kBTC.
