can they do microwave?

if you do the exact right color you can make certain things melt very precisely.

An application that came to mind is tunneling (through rock and earth). You could absolutely tune the wavelength to whatever material your drilling through absorbs best, to help ease and speed. Would need a good amount of energy but I could see that utilized in some fashion in the next 10-20 years

https://en.wikipedia.org/wiki/Maser