it's possible that you're missing the trick of "two photon excitation" which the paper sort of breezes past, but is the solution for "i only want the effect to happen right where i've created a tiny focal sphere of this laser." see e.g. https://en.wikipedia.org/wiki/Two-photon_excitation_microsco...

The triplets described in this paper seem to build on the "standard" 2P effect.