DIRECT OBSERVATION OF RADIATION LOCKING USING PHASE-SENSITIVE DETECTION

Radiation locking, the optical analogy of spin locking, is observed in the F-7(0) double left right arrow D-5(0) optical transition of KEu(W O4)(2) using phase-sensitive detection. The relaxation rate of the rad iation-locked signal when compared to calculations based on the optica l Bloch equations and photon-echo measurements of T-2 was found to be significantly slower than predicted. The relaxation rate of the radiat ion-locked signal is also compared with rotary-echoes measurements. Th e inadequacy of the optical Bloch equations to describe the present ex periment is similar to observations made using free induction decay in Pr3+ : LaF3 and ruby. (C) 1998 Elsevier Science B.V. All rights reser ved.