Optimal estimation of entanglement and discord in two-qubit states
Abstract
Recently, the fast development of quantum technologies led to the need for tools allowing the characterization of quantum resources. In particular, the ability to estimate non-classical aspects, e.g. entanglement and quantum discord, in two-qubit systems, is relevant to optimise the performance of quantum information processes. Here we present an experiment in which the amount of entanglement and discord are measured exploiting different estimators. Among them, some will prove to be optimal, i.e., able to reach the ultimate precision bound allowed by quantum mechanics. These estimation techniques have been tested with a specific family of states ranging from nearly pure Bell states to completely mixed states. This work represents a significant step in the development of reliable metrological tools for quantum technologies.
Keywords
Cite
@article{arxiv.1810.09331,
title = {Optimal estimation of entanglement and discord in two-qubit states},
author = {Salvatore Virzí and Enrico Rebufello and Alessio Avella and Fabrizio Piacentini and Marco Gramegna and Ivano Ruo Berchera and Ivo Pietro Degiovanni and Marco Genovese},
journal= {arXiv preprint arXiv:1810.09331},
year = {2019}
}