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arXiv · 1605.09278

Universal Quantum Computing with Arbitrary Continuous-Variable Encoding

Hoi-Kwan Lau·Martin B. Plenio
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Abstract

Implementing a qubit quantum computer in continuous-variable systems conventionally requires the engineering of specific interactions according to the encoding basis states. In this work, we present a unified formalism to conduct universal quantum computation with a fixed set of operations but arbitrary encoding. By storing a qubit in the parity of two or four qumodes, all computing processes can be implemented by basis state preparations, continuous-variable exponential-swap operations, and swap-tests. Our formalism inherits the advantages that the quantum information is decoupled from collective noise, and logical qubits with different encodings can be brought to interact without decoding. We also propose a possible implementation of the required operations by using interactions that are available in a variety of continuous-variable systems. Our work separates the `hardware' problem of engineering quantum-computing-universal interactions, from the `software' problem of designing encodings for specific purposes. The development of quantum computer architecture could hence be simplified.

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Hoi-Kwan Lau, Martin B. Plenio. 2016-05-30. Universal Quantum Computing with Arbitrary Continuous-Variable Encoding. https://doi.org/10.1103/physrevlett.117.100501

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