Unsupervised classification of quantum data

We introduce the problem of unsupervised classification of quantum data, namely, of systems whose quantum states are unknown. We derive the optimal single-shot protocol for the binary case, where the states in a disordered input array are of two types. Our protocol is universal and able to automatic...

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Detalles Bibliográficos
Autores: Sentís, Gael|||0000-0002-4982-6570, Monras Blasi, Àlex, Muñoz Tapia, Ramon|||0000-0002-3048-9236, Calsamiglia, John|||0000-0003-1735-1360, Bagan, E.|||0000-0002-7900-3567
Tipo de recurso: artículo
Fecha de publicación:2019
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:214914
Acceso en línea:https://ddd.uab.cat/record/214914
https://dx.doi.org/urn:doi:10.1103/PhysRevX.9.041029
Access Level:acceso abierto
Palabra clave:Quantum Information
Statistical Physics
Descripción
Sumario:We introduce the problem of unsupervised classification of quantum data, namely, of systems whose quantum states are unknown. We derive the optimal single-shot protocol for the binary case, where the states in a disordered input array are of two types. Our protocol is universal and able to automatically sort the input under minimal assumptions, yet partially preserves information contained in the states. We quantify analytically its performance for an arbitrary size and dimension of the data. We contrast it with the performance of its classical counterpart, which clusters data that have been sampled from two unknown probability distributions. We find that the quantum protocol fully exploits the dimensionality of the quantum data to achieve a much higher performance, provided the data are at least three dimensional. For the sake of comparison, we discuss the optimal protocol when the classical and quantum states are known.