Controlling entanglement between two separated atoms by quantum-jump-based feedback

We consider a model consisting of two (two-level) atoms which are placed in two separated heavily damped cavities respectively. We show that the quantum-jump-based feedback based on joint measurement can be used to generate a steady entangled state between two atoms against decoherence. We analyse the effects of general local control Hamiltonians in the performance of entanglement production and show that by choosing a proper control Hamiltonian the steady maximal entanglement between two separated atoms can be protected.

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