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Mocking up a Dephasing Channel with a Minimal-Sized Environment |
| WU Zhen** |
| State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 Graduate School of the Chinese Academy of Sciences, Beijing 100049 |
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Abstract In order to model the most general quantum operation on a d-dimensional system, a d2-dimensional environment is usually needed. We focus on the quantum dephasing process and find that this channel can be modeled by an environment with the size of at most d dimensions. An experimentally accessible matrix D is defined to characterize the dephasing channel and the minimal number of Kraus operators of the channel from the matrix D for mocking up the dephasing channel is presented in the minimal-sized environment. An experimental simulation of dephasing channels by means of nuclear magnetic resonance techniques is carried out to justify the idea.
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Received: 29 May 2012
Published: 31 July 2012
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| PACS: |
03.65.Yz
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(Decoherence; open systems; quantum statistical methods)
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03.67.Ac
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(Quantum algorithms, protocols, and simulations)
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03.65.Wj
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(State reconstruction, quantum tomography)
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03.67.Lx
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(Quantum computation architectures and implementations)
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