Optical free induction decay of the ⁴G _{5 2} ↔ ⁶H _{5 2} transition of LaF₃:Sm³⁺

The population decay time (T1) and optical dephasing time (T2) of the 4G 5 2 ↔ 6H 5 2 transition LaF3+ at 5598 Å has been measured. At 1.6 K, T1 = 7.7 ms and T2 = 110 ns. The oscillator strength of this transition is 6 × 10-9. The dephasing time was measured by observing the optical free induction decay following intracavity laser frequency switching or intracavity phase switching. © 1986.