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arXiv · 1909.09112

Hybrid Quantum Error Correction in Qubit Architectures

Lasse Bjørn Kristensen·Morten Kjaergaard·Christian Kraglund Andersen·Nikolaj Thomas Zinner
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Abstract

Noise and errors are inevitable parts of any practical implementation of a quantum computer. As a result, large-scale quantum computation will require ways to detect and correct errors on quantum information. Here, we present such a quantum error correcting scheme for correcting the dominant error sources, phase decoherence and energy relaxation, in qubit architectures, using a hybrid approach combining autonomous correction based on engineered dissipation with traditional measurement-based quantum error correction. Using numerical simulations with realistic device parameters for superconducting circuits, we show that this scheme can achieve a 5- to 10-fold increase in storage-time while using only six qubits for the encoding and two ancillary qubits for the operation of the autonomous part of the scheme, providing a potentially large reduction of qubit overhead compared to typical measurement-based error correction schemes. Furthermore, the scheme relies on standard interactions and qubit driving available in most major quantum computing platforms, making it implementable in a wide range of architectures.

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Lasse Bjørn Kristensen, Morten Kjaergaard, Christian Kraglund Andersen, Nikolaj Thomas Zinner. 2019-09-19. Hybrid Quantum Error Correction in Qubit Architectures. https://arxiv.org/abs/1909.09112

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