Purity speed limit for open quantum systems

TYPETheor./Math. Physics Seminar
Speaker:Dr. Raam Uzdin
Location:Lewiner Seminar Room (412)

The defining property of an open quantum system is the time variation of its purity. We derive generic speed limits on the rate of purity change for systems described by Lindblad equation and Lindblad-like equation (non-Markovian dynamics). These bounds depend solely on the generators of the non unitary dynamics and are independent of the particular states of the systems. They are thus perfectly suited to investigate dephasing, thermalization, and decorrelation processes of arbitrary states. We show that our best speed limit can be attained and is therefore tight. As an application of our results we study the speed of classical and quantum correlation erasure.