抄録
Nuclear magnetic resonance on oriented nuclei (NMR-ON) of La existing as a dilute impurity in Fe was observed for the first time. NMR-ON experiments were performed by detecting the 1596 keV γ rays from the β decay of 140La in external magnetic fields of 0.1, 0.2, 0.4 and 0.6 T. From the external magnetic-field dependence of the resonance frequency, the magnetic hyperfine field and the Knight shift were deduced to be Bhf=−47±1 T and K=−4.0±3.4%, respectively. The effective relaxation time of 140LaFe at 8 mK in an external magnetic field of 0.2 T was determined to be 8.8±1.5 min using a single-exponential fit. The present value of the magnetic hyperfine field agrees with that deduced from a two-site model by the low-temperature nuclear orientation method.
