Evolution of quantum entanglement of two finite dimensional systems

Manuel Erhard, Mario Krenn, Anton Zeilinger

Sandeep K. Goyal, Sibasish Ghosh A

The phenomenon of entanglement sudden death (ESD) in finite dimensional composite open systems is described here for both bi-partite as well as multipartite cases, where individual subsystems undergo Lindblad type heat bath evolution. ESD is found to be generic for non-zero temperature of the bath. At T=0, one-sided action of the heat bath on pure entangled states of two qubits does not show ESD.

Shion Yamashika, Filiberto Ares, Pasquale Calabrese

We study the time evolution of the R\'enyi entanglement entropies following a quantum quench in a two-dimensional (2D) free fermion system. By employing dimensional reduction, we effectively transform the 2D problem into decoupled chains, a technique applicable when the system exhibits translational invariance in one direction. Various initial configurations are examined, revealing that the behavior of entanglement entropies can often be explained by adapting the one-dimensional quasiparticle picture. However, intriguingly, for specific initial states the entanglement entropy saturates to a finite value without the reduced density matrix converging to a stationary state. We discuss the conditions necessary for a stationary state to exist and delve into the necessary modifications to the quasiparticle picture when such a state is absent.

Paweł Caban, Jakub Rembieliński, Kordian A. Smoliński +1 more

Thomas Konrad, Fernando de Melo, Markus Tiersch +3 more

A. Kowalewska-Kudłaszyk, W. Leoński

We discuss a system comprising two nonlinear (Kerr-like) oscillators coupled mutually by a nonlinear interaction. The system is excited by an external coherent field that is resonant to the frequency of one of the oscillators. We show that the coupler evolution can be closed within a finite set of $n$-photon states, analogously as in the nonlinear quantum scissors model. Moreover, for this type of evolution our system can be treated as a Bell-like state generator. Thanks to the nonlinear nature of both oscillators and their internal coupling, these states can be generated even if the system exhibits its energy dissipating nature, contrary to systems with linear couplings.