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arXiv · 0807.0379

Dynamics of nonequilibrium thermal entanglement

Ilya Sinaysky·Francesco Petruccione·Daniel Burgarth
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Abstract

The dynamics of a simple spin chain (2 spins) coupled to bosonic baths at different temperatures is studied. The analytical solution for the reduced density matrix of the system is found. The dynamics and temperature dependence of spin-spin entanglement is analyzed. It is shown that the system converges to a steady-state. If the energy levels of the two spins are different, the steady-state concurrence assumes its maximum at unequal bath temperatures. It is found that a difference in local energy levels can make the steady-state entanglement more stable against high temperatures.

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Ilya Sinaysky, Francesco Petruccione, Daniel Burgarth. 2009-05-05. Dynamics of nonequilibrium thermal entanglement. https://doi.org/10.1103/physreva.78.062301

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