[tzot]

As I understand it, when you heat water, you give energy to all of the water molecules that start moving faster in their random direction. So molecules that were directed towards outside the water mass are “directly” extracted, and the rest will bounce around in the increasing pressure until they are “indirectly” extracted (I used “directly” and “indirectly” non-scientifically here, just to make a distinction.) It takes quite a lot of energy which leads to evaporation over time.

I think what they found is a set of circumstances where the energy of the light “chips off pieces” of water, so the energy needed is much less. A small broken-off “piece” (or cluster of water molecules) has a very large ratio of surface area over volume, so the rest of the evaporation is taken care of by the surrounding environment as-is.