Ultraslow optical dephasing of LaF3: Pr3+

Optical free-induction dephasing times as long as 16 μsec, corresponding to an optical homogenous linewidth of 10 kHz, have been observed for the H43D21 transition of Pr3+ ions in LaF3 at 2K. Measurements are facilitated by a frequency-locked cw dye laser and a new form of laser frequency switching. Zeeman studies reveal a Pr-F dipole-dipole dephasing mechanism where the Pr nuclear moment is enhanced in both D21 and H43. © 1979 The American Physical Society.