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arXiv · 1104.1752

Non-Markovian dynamical effects and time evolution of entanglement entropy of a dissipative two-state system

Zhiguo Lü·H. Zheng
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Abstract

We investigate the dynamical information exchange between a two-state system and its environment which is measured by von Neumann entropy. It is found that in the underdamping regime, the entropy dynamics exhibits an extremely non-Markovian oscillation-hump feature, in which oscillations manifest quantum coherence and a hump of envelop demonstrates temporal memory of bath. It indicates that the process of entropy exchange is bidirectional. When the coupling strength increases a certain threshold, the hump along with ripple disappears, which is indicative of the coherent-incoherent dynamical crossover. The long-time limit of entropy evolution reaches the ground state value which agrees with that of numerical renormalization group.

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Zhiguo Lü, H. Zheng. 2011-04-10. Non-Markovian dynamical effects and time evolution of entanglement entropy of a dissipative two-state system. https://doi.org/10.1209/0295-5075/86/60009

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