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arXiv · 1601.05163

Decoherence dynamics of interacting qubits coupled to a bath of local optical phonons

Muzaffar Qadir Lone·Sudhakar Yarlaggada
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Abstract

We study decoherence in an interacting qubit system described by infinite range Heisenberg model (IRHM) in a situation where the system is coupled to a bath of local optical phonons. Using perturbation theory in polaron frame of reference, we derive an effective Hamiltonian that is valid in the regime of strong spin-phonon coupling under non-adiabatic conditions. It is shown that the effective Hamiltonian commutes with the IRHM upto leading orders of perturbation and thus has the same eigenstates as the IRHM. Using a quantum master equation with Markovian approximation of dynamical evolution, we show that the off diagonal elements of the density matrix donot decay in the energy eigen basis of IRHM.

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Muzaffar Qadir Lone, Sudhakar Yarlaggada. 2016-01-20. Decoherence dynamics of interacting qubits coupled to a bath of local optical phonons. https://arxiv.org/abs/1601.05163

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