Black = no light. Laser = light. With current tech there's quite a few wavelengths available, I'd say research funding and necessity to have a laser of every single visible wavelength are the only thing holding us back.
Every once in a while this seems to come up. It really counfounds me. Has anyone seen a 'black lightbulb", "black LED", "black spotlight", etc; has anyone ever seen "black light"? (And I do not mean UV.)
I just get amazed that this comes up so regularly.. the idea of something that could "cast shadows" actively, basically "emit shadows" There is no such thing as black light.... Very odd...
The wave cancellation theory would never work unless you had a completely static or controlled environment. Reason: any changes to the environment could only be transmitted back to the light source at the speed of light, and even the slightest variant between the modeled environment and the actual environment would produce more apparent light rather than less.
Plus there's this little thing called Heisenberg's uncertainty principal that starts being relevant at those scales.