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arXiv · 1804.03680

Hierarchical quantum classifiers

Edward Grant·Marcello Benedetti·Shuxiang Cao·Andrew Hallam·Joshua Lockhart·Vid Stojevic·Andrew G. Green·Simone Severini
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Abstract

Quantum circuits with hierarchical structure have been used to perform binary classification of classical data encoded in a quantum state. We demonstrate that more expressive circuits in the same family achieve better accuracy and can be used to classify highly entangled quantum states, for which there is no known efficient classical method. We compare performance for several different parameterizations on two classical machine learning datasets, Iris and MNIST, and on a synthetic dataset of quantum states. Finally, we demonstrate that performance is robust to noise and deploy an Iris dataset classifier on the ibmqx4 quantum computer.

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Edward Grant, Marcello Benedetti, Shuxiang Cao, Andrew Hallam, Joshua Lockhart, Vid Stojevic, Andrew G. Green, Simone Severini. 2018-04-10. Hierarchical quantum classifiers. https://doi.org/10.1038/s41534-018-0116-9

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