Unsupervised Classification of Quantum Data

Autor: Gael Sentís, Alex Monràs, Ramon Muñoz-Tapia, John Calsamiglia, Emilio Bagan
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Physical Review X, Vol 9, Iss 4, p 041029 (2019)
Druh dokumentu: article
ISSN: 2160-3308
DOI: 10.1103/PhysRevX.9.041029
Popis: 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.
Databáze: Directory of Open Access Journals