It has a built in Heisenberg compensator.
Jokes aside. Krauss "The Physics of Star Trek" is actually quite a good book. The transporter is covered in one of chapters. And one side-effect of reading it is that you do learn something about real physics as well.
Also the "Heisenberg compensator" is actually quite a clever device.
Has anyone ever seen it mentioned in a QM course*?
*Not as a "real" device of course, but explaining why one would/wouldn't be needed for the transporter sounds like a fun assignment.
EDIT: Another thing about the book that i thought was funny, was they spent all this time on the specs of the equipment, the crucial aspect of "how" a particular technology worked was kind of brushed off.
Edit: Janus was faster...