biphotonic excitation
Simultaneous (coherent) @A00036@ of two @P04627@ (either same or different @W06659@), the energy of excitation being the sum of the energies of the two photons. Also called @T06541@.
This term is sometimes also used for a two-step absorption.
PAC, 2007, 79, 293. (Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)) on page 308 [Terms] [Paper]