Theoretical analysis demonstrates two-photon absorption in CaF2:Eu++, aligning with experimental outcomes.
The possibility of observing two-photon processes using the intense beam of the ruby optical maser is considered theoretically for two general types of experiment. The essential approximation in the theory is the hypothesis that excited states exist which connect both the initial and final states by electric dipole transitions having a total oscillator strength f~1. Simple formulas are obtained for the two-photon absorption which do not depend on the details of the electronic structure. Recent experiments on the CaF₂: Eu⁺⁺ system are in quantitative agreement with the predictions of the theory.
No takes yet. Share an insight, caveat, or question.
David A. Kleinman (1962) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: