Characterization of Fine Structures in Electronic States by Raman Heterodyne Detection Using Optical Transition.

在1.5K下，在Pr^&lt；3+&gt；20925 cm；-1&gt；上探测到掺入LaF_3的Pr^&lt；3+&gt；的^&lt；139&gt；La原子核在Pr^&lt；3+&gt；周围的四极跃迁是光射频诱导的相干喇曼拍频。由于激发态的有效核磁矩^&lt；141&gt；Pr比基态小，Pr-La相互作用随Pr^&lt；3+&gt；的降低而减小。光激发，这使得La的四极跃迁与Pr的光学跃迁耦合。观察到四个磁性不等价的La核，揭示了La原子在杂质Pr^&lt；3+&Gt；离子周围的不同局域环境。

The quadrupole transitions of ^<139> La nuclei around Pr^<3+> doped in LaF_3 have been detected as an optical-rf induced coherent Raman beat on the Pr^<3+>^3H_4-^3P_0 transition (20925 cm^<-1>) at 1.5 K.Because the effective ^<141>Pr nuclear magnetic moment is smaller in the excited ^3P_0 state than in the ground state, the Pr-La interaction decreases upon Pr^<3+> optical excitation, which makes the La quadrupole transitions couple with the Pr optical transition. Four magnetically inequivalent La nuclei were observed, revealing different local environments of La atoms around impurity Pr^<3+> ions.