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Experimental quantum coding against qubit loss error.

ABSTRACT: The fundamental unit for quantum computing is the qubit, an isolated, controllable two-level system. However, for many proposed quantum computer architectures, especially photonic systems, the qubits can be lost or can leak out of the desired two-level systems, posing a significant obstacle for practical quantum computation. Here, we experimentally demonstrate, both in the quantum circuit model and in the one-way quantum computer model, the smallest nontrivial quantum codes to tackle this problem. In the experiment, we encode single-qubit input states into highly entangled multiparticle code words, and we test their ability to protect encoded quantum information from detected 1-qubit loss error. Our results prove in-principle the feasibility of overcoming the qubit loss error by quantum codes.

SUBMITTER: Lu CY

PROVIDER: S-EPMC2516277 | biostudies-other | 2008 Aug

REPOSITORIES: biostudies-other

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Experimental quantum coding against qubit loss error.

Lu Chao-Yang CY Gao Wei-Bo WB Zhang Jin J Zhou Xiao-Qi XQ Yang Tao T Pan Jian-Wei JW

Proceedings of the National Academy of Sciences of the United States of America 20080805 32

The fundamental unit for quantum computing is the qubit, an isolated, controllable two-level system. However, for many proposed quantum computer architectures, especially photonic systems, the qubits can be lost or can leak out of the desired two-level systems, posing a significant obstacle for practical quantum computation. Here, we experimentally demonstrate, both in the quantum circuit model and in the one-way quantum computer model, the smallest nontrivial quantum codes to tackle this proble ...[more]

PMID: 18682562

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