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arXiv · 0811.3581

Relaxation due to random collisions with a many-qudit environment

Giuseppe Gennaro·Giuliano Benenti·G. Massimo Palma
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Abstract

We analyze the dynamics of a system qudit of dimension mu sequentially interacting with the nu-dimensional qudits of a chain playing the ore of an environment. Each pairwise collision has been modeled as a random unitary transformation. The relaxation to equilibrium of the purity of the system qudit, averaged over random collisions, is analytically computed by means of a Markov chain approach. In particular, we show that the steady state is the one corresponding to the steady state for random collisions with a single environment qudit of effective dimension nu_e=nu*mu. Finally, we numerically investigate aspects of the entanglement dynamics for qubits (mu=nu=2) and show that random unitary collisions can create multipartite entanglement between the system qudit and the qudits of the chain.

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Giuseppe Gennaro, Giuliano Benenti, G. Massimo Palma. 2008-11-21. Relaxation due to random collisions with a many-qudit environment. https://doi.org/10.1103/physreva.79.022105

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