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arXiv · 0907.1764

Efficient compression of quantum information

Martin Plesch·Vladimir Buzek
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Abstract

We propose a scheme for an exact efficient transformation of a tensor product state of many identically prepared qubits into a state of a logarithmically small number of qubits. Using a quadratic number of elementary quantum gates we transform N identically prepared qubits into a state, which is nontrivial only on the first log(N+1) qubits. This procedure might be useful for quantum memories, as only a small portion of the original qubits has to be stored. Another possible application is in communicating a direction encoded in a set of quantum states, as the compressed state provides a high-effective method for such an encoding.

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Martin Plesch, Vladimir Buzek. 2010-02-02. Efficient compression of quantum information. https://doi.org/10.1103/physreva.81.032317

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