NMR Measurement of the Hyperfine Constant of an Excited State of an Impurity Ion in a Solid

Abstract
An optically detected NMR measurement of the hyperfine tensor for an excited state of an impurity rare-earth ion (Pr3+) in a solid (LiYF4) is reported. The results have been used to obtain for the first time a measured value of the hyperfine interaction constant Aj=616±51 MHz of the D21 excited state. This is somewhat smaller than the calculated value of 754 MHz.