two-photon absorption

Posted by Martin Wessendorf-2 on
URL: http://confocal-microscopy-list.275.s1.nabble.com/two-photon-absorption-tp7581862.html

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Dear List--

Is there a physicist out there who can offer an intuitive explanation of
how 2-photon absorption occurs?  I expect we all know that it isn't that
there isn't any half-excited state that allows one photon to boost an
electron half-way to the excited state, and the next photon to finish
the job.  My sense is that it has to do with time-energy uncertainty (a
la Heisenberg) but my quantum mechanics is elementary-school level.

Thanks!

Martin Wessendorf

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