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arXiv · 2107.07279

Resource-efficient Purification-based Quantum Error Mitigation

Zhenyu Cai
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Abstract

To achieve the practical applications of near-term noisy quantum devices, low-cost ways to mitigate the noise damages in the devices are essential. In many applications, the noiseless state we want to prepare is often a pure state, which has recently inspired a range of purification-based quantum error mitigation proposals. The existing proposals either are limited to the suppressions of only the leading-order state preparation errors, or require a large number of long-range gates that might be challenging to implement depending on the qubit architecture. This article will provide an overview of the different purification-based quantum error mitigation schemes and propose a resource-efficient scheme that can correct state preparation errors up to any order while requiring only half of the qubits and less than half of the long-range gates compared to before.

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Zhenyu Cai. 2021-07-15. Resource-efficient Purification-based Quantum Error Mitigation. https://arxiv.org/abs/2107.07279

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