This question has, no doubt, been answered before here ... but my quick search came up with nothing. I'm interested to know what 'two-slit' experiments have been done, and published, using things other than photons. In particular, versions in which 'no more than one in apparatus at any time' is an explicit part of the experiment. I'm pretty sure there are some good ones, using electrons. But what about other particles? Have there been any with atoms (esp with the constraint 'no more than one in apparatus at any time')? References to papers available online (free, and not needing a subscription) would be much appreciated.