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arXiv · 1407.6862

Dynamics of an open quantum system interacting with a quantum environment

Athreya Shankar·S. Lakshmibala·V. Balakrishnan
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Abstract

We examine the dynamics of subsystems of bipartite and tripartite quantum systems with nonlinear Hamiltonians. We consider two models which capture the generic features of open quantum systems: a three-level atom interacting with a single-mode radiation field, and a three-level atom interacting with two field modes which do not directly interact with each other. The entanglement of specific initially unentangled states of the atom-field system is examined through the time-varying subsystem von Neumann entropy (SVNE). The counterparts of near-revivals and fractional revivals of the initial state are clearly identifiable in the SVNE in all cases where revival phenomena occur. The Mandel $Q$ parameter corresponding to the photon number of a radiation field is obtained as a function of time in both models. In those cases where revivals are absent, a time series analysis of the mean photon number reveals a variety of ergodicity properties (as manifested in return maps, recurrence-time distributions and Lyapunov exponents), depending on the strength of the nonlinearity and the degree of coherence of the initial state of the radiation field(s).

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Athreya Shankar, S. Lakshmibala, V. Balakrishnan. 2014-07-25. Dynamics of an open quantum system interacting with a quantum environment. https://doi.org/10.1088/0953-4075%2F47%2F21%2F215505

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