Optically detected coherent transients in nuclear hyperfine levels

Using optical detection, we have observed rf nutation, free-induction decay, and echoes, on the 16.70-MHz nuclear hyperfine transition of dilute Pr3+ in LaF3 at 2 K. From a comparison of free-induction decay and echo decay we find that the previously observed linewidth of 200 kHz is inhomogeneous and that the homogeneous width is 19 kHz. On the basis of these measurements it is suggested that optical dephasing times for the D21H43 and P03H43 transitions are as long as ∼20 μ sec. © 1978 The American Physical Society.