Data re-uploading for a universal quantum classifier

A single qubit provides sufficient computational capabilities to construct a universal quantum classifier when assisted with a classical subroutine. This fact may be surprising since a single qubit only offers a simple superposition of two states and single-qubit gates only make a rotation in the Bl...

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Bibliographic Details
Authors: Pérez Salinas, Adrián, Cervera Lierta, Alba|||0000-0002-8835-2910, Gil Fuster, Elies, Latorre, José Ignacio
Format: article
Publication Date:2020
Country:España
Institution:Universitat Politècnica de Catalunya (UPC)
Repository:UPCommons. Portal del coneixement obert de la UPC
Language:English
OAI Identifier:oai:upcommons.upc.edu:2117/331156
Online Access:https://hdl.handle.net/2117/331156
https://dx.doi.org/10.22331/q-2020-02-06-226
Access Level:Open access
Keyword:Quantum computers
Universal quantum classifier
Qubit
Multiple data re-uploading
Quantum Computation
Ordinadors quàntics
Àrees temàtiques de la UPC::Informàtica
Description
Summary:A single qubit provides sufficient computational capabilities to construct a universal quantum classifier when assisted with a classical subroutine. This fact may be surprising since a single qubit only offers a simple superposition of two states and single-qubit gates only make a rotation in the Bloch sphere. The key ingredient to circumvent these limitations is to allow for multiple data re-uploading . A quantum circuit can then be organized as a series of data re-uploading and single-qubit processing units. Furthermore, both data re-uploading and measurements can accommodate multiple dimensions in the input and several categories in the output, to conform to a universal quantum classifier. The extension of this idea to several qubits enhances the efficiency of the strategy as entanglement expands the superpositions carried along with the classification. Extensive benchmarking on different examples of the single- and multi-qubit quantum classifier validates its ability to describe and classify complex data