Answers are grounded in this paper and cite their sources.
A density-matrix analysis is given of some properties of photon echoes arising from nearly degenerate ground and/or excited states. Modulations of the echo intensity as a function of pulse separation time are predicted as well as more complicated effects near level crossings. In particular, the analysis is applied to the 2.06-kG level crossing in the ground state of ruby.
No takes yet. Share an insight, caveat, or question.
Lambert et al. (1971) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: