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arXiv · 1112.5889

Pure Gaussian state generation via dissipation: A quantum stochastic differential equation approach

Naoki Yamamoto
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Abstract

Recently the complete characterization of a general Gaussian dissipative system having a unique pure steady state was obtained in [Koga and Yamamoto 2012, Phys. Rev. A 85, 022103]. This result provides a clear guideline for engineering an environment such that the dissipative system has a desired pure steady state such as a cluster state. In this paper, we describe the system in terms of a quantum stochastic differential equation (QSDE) so that the environment channels can be explicitly dealt with. Then a physical meaning of that characterization, which cannot be seen without the QSDE representation, is clarified; more specifically, the nullifier dynamics of any Gaussian system generating a unique pure steady state is passive. In addition, again based on the QSDE framework, we provide a general and practical method to implement a desired dissipative Gaussian system, which has a structure of quantum state transfer.

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Naoki Yamamoto. 2012-03-06. Pure Gaussian state generation via dissipation: A quantum stochastic differential equation approach. https://doi.org/10.1098/rsta.2011.0529

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