Varon wrote:
It's realistic science, actually. They've done it with a few atoms. It uses quantum stuff to work.
When I've seen explanations for why a "transporter beam" could 
not possibly work, both in science fiction and in nominally factual publications, quantum effects are usually mentioned as the final blow preventing the technology from being a possibility, at least for transporting human beings. They tend to be (though not all are) resting on the assumption that consciousness, personality, and free will come down to that level (everything above being seen as deterministic I think), so the transfer would have to be without error down to the quantum level ... and the Heisenberg Uncertainty Principle says that it's not possible for us to measure the position of a quantum particle whose velocity we know, or the velocity of a quantum particle whose position we know.
There's also the problem that "quantum stuff" is (as far as I can see) the single branch of applied science having the most trouble "scaling up." A few atoms are a useful first step, but are hardly a proof of concept.
None of this should necessarily stop an author from using "transporter beams" in his or her story; like it or not they've become a common element---a "trope"---in certain branches of science fiction, and so are, like faster-than-light travel, something readers have been trained to expect in some contexts ... and quantum physics and/or mechanics is as good a source as any for the hand-wave-y explanation aka doubletalk with which the technology is described. (Far better than Lewis's use of "the less observed properties of solar radiation" in 
Out of the Silent Planet)