Purification through Zeno-like measurements

Phys Rev Lett. 2003 Feb 14;90(6):060401. doi: 10.1103/PhysRevLett.90.060401. Epub 2003 Feb 10.

Abstract

A series of frequent measurements on a quantum system (Zeno-like measurements) is shown to result in the "purification" of another quantum system in interaction with the former. Even though the measurements are performed on the former system, their effect drives the latter into a pure state, irrespectively of its initial (mixed) state, provided certain conditions are satisfied.