Take look at Oscillation. Hertz.
Demateralization.
Nanotechnology. (We can even today do molecular thin layers of things)
Our computer processor today run at 3000000000 Hertz. Thats the amounts of times up and own/on and off/circular motion.
I guess the big problem is to put everyhing back into place. And how to activate a brain dead person? Maybe you could tune the mind in after some time. The brain waves have to be the same. Maybe a computer program will preform a proxamiation that will in the end be so close to the original mind that it dosen´t matter. The character might experience this as dreams - that suddenly crashes - A new dream will start to continue a bit longer but only to crash again - with no memories of the former dream.
The original mind prior to the whole process was saved. The brainwaves results of countless of small expriments (brain reaction to events) made by the computer - and longterm memory. 790
When the brain starts to work - it compares it to the saved brain data (and brain wave functions) - and shut down - to redo process until it is on a whole the same as the original.
When it comes rematerizaltion. Thats a tough one. There is extreme amounts of atoms in a human body. It would be near impossible if not impossible to save such data - of how they are built up. After all life is quiet old. And I guess our atoms is as many as planets and stars in our universe or something like that.
I suggest the character (characters mind) would have to be inserted in a new body - or a clone (that have gotten through similar life events in a simulated enviroment). If you want more realism I think you might want to skip the container. If you stay with the container - maybe the atoms and molecules are used (turned into water and oxygen - and cole to to CO2 - for plants to breath to become food for the clone). Basically you characters materia would be recycled into a clone tha becomes himself again.
You could also take a look at this and use it somehow. https://en.wikipedia.org/wiki/Isotope_separation 790