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arXiv · 2204.00015

Measuring magic on a quantum processor

Salvatore F. E. Oliviero·Lorenzo Leone·Alioscia Hamma·Seth Lloyd
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Abstract

Magic states are the resource that allows quantum computers to attain an advantage over classical computers. This resource consists in the deviation from a property called stabilizerness which in turn implies that stabilizer circuits can be efficiently simulated on a classical computer. Without magic, no quantum computer can do anything that a classical computer cannot do. Given the importance of magic for quantum computation, it would be useful to have a method for measuring the amount of magic in a quantum state. In this work, we propose and experimentally demonstrate a protocol for measuring magic based on randomized measurements. Our experiments are carried out on two IBM Quantum Falcon processors. This protocol can provide a characterization of the effectiveness of a quantum hardware in producing states that cannot be effectively simulated on a classical computer. We show how from these measurements one can construct realistic noise models affecting the hardware.

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Salvatore F. E. Oliviero, Lorenzo Leone, Alioscia Hamma, Seth Lloyd. 2022-03-31. Measuring magic on a quantum processor. https://doi.org/10.1038/s41534-022-00666-5

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