First allow me to apologize should this thread be in the wrong forum, I am not entirely sure whether Quantum Physics is the right one. I am also unaware of the exact level to which this question belongs, which is why I went for intermediate. Please inform me if this should be changed to advanced. For a pet project I'm trying to find a way in which to create simple "holograms". The most feasible way of doing this in a garage seems to be with lasers intersecting to excite a local area within a medium to make it luminescent. Now, there are some questions I have regarding this problem but probably the most important is regarding the medium in which this could be most easily achieved. Ideally, I would of course be using simple air, but seeing as I've got no access to very high power lasers this might be out of reach. Since I have been unable to find sufficient articles relating to how one would approach such a problem, I would like some input and possibly discussion concerning the medium.