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why in photoelectric effect an electron absorbs only one photon.
- sachin (age 16)
In principle you can have absorption of multiple photons in the photoelectric effect. In practice the probability is very very small under ordinary circumstances. If you had a strong enough laser beam you could probably observe the effect.
Multiple (two) photon absorption to drive fluorescence is now used in some special microscopes. It does require well-focused lasers, as well as molecules which are good at absorbing those two photons. Mike W.
(published on 03/20/09)
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