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Decoherence under many-body system-environment interactions: a stroboscopic representation based on a fictitiously homogenized interaction rate

Gonzalo A. Alvarez·Ernesto P. Danieli·Patricia R. Levstein·Horacio M. Pastawski
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Abstract

An environment interacting with portions of a system leads to multiexponential interaction rates. Within the Keldysh formalism, we fictitiously homogenize the system-environment interaction yielding a uniform decay rate facilitating the evaluation of the propagators. Through an injection procedure we neutralize the fictitious interactions. This technique justifies a stroboscopic representation of the system-environment interaction which is useful for numerical implementation and converges to the natural continuous process. We apply this procedure to a fermionic two-level system and use the Jordan-Wigner transformation to solve a two-spin swapping gate in the presence of a spin environment.

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Gonzalo A. Alvarez, Ernesto P. Danieli, Patricia R. Levstein, Horacio M. Pastawski. 2007-07-12. Decoherence under many-body system-environment interactions: a stroboscopic representation based on a fictitiously homogenized interaction rate. https://doi.org/10.1103/physreva.75.062116

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