Optimal measurements to access classical correlations of two-qubit states

By Xiao-Ming Lu, Jian Ma, Zhengjun Xi, Xiaoguang Wang. 2010

153 citations recorded by the source corpus.

We analyze the optimal measurements to access classical correlations in arbitrary two-qubit states. Two-qubit states can be transformed into the canonical forms via local unitary operations. For the canonical forms, we investigate the probability distribution of the optimal measurements. The probability distribution of the optimal measurements is found to be centralized in the vicinity of a specific von Neumann measurement, which we call the maximal-correlation-direction measurement (MCDM). We prove that, for the states with zero discord and maximally mixed marginals, the MCDM is the optimal measurement. Furthermore, we give an upper bound of quantum discord based on the MCDM, and investigate its performance for approximating the quantum discord.

Subfields: Artificial Intelligence, Atomic and Molecular Physics, and Optics

View Paper: https://www.semanticscholar.org/paper/b1f1ad53d3076e73c077b739dcddf101e1ff8cc5

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Artificial Intelligence

1. Kavan Modi
2. Tomasz Paterek
3. H. Cable
4. Aharon Brodutch
5. Vlatko Vedral

In Atomic and Molecular Physics, and Optics

1. Kavan Modi
2. Tomasz Paterek
3. H. Cable
4. Aharon Brodutch
5. Vlatko Vedral

Citations in the corpus

• The classical-quantum boundary for correlations: Discord and related measures (2011, methodology): “In (Lu et al., 2011), the authors study statistically the usefulness of a measurement termed the maximal-correlationsdirection measurement (MCDM).”