# Sharma-Mittal Quantum Discord

## TL;DR

This paper introduces Sharma-Mittal quantum discord, a generalized measure of quantum correlations based on Sharma-Mittal entropy, providing analytic expressions for various quantum states and comparing it with other quantum correlation measures.

## Contribution

It presents the first analytic formulation of Sharma-Mittal quantum discord for key quantum states and unifies existing discord measures as special cases.

## Key findings

- Sharma-Mittal quantum discord generalizes R{é}nyi, Tsallis, and von-Neumann discord.
- Analytic expressions derived for two-qubit, Werner, isotropic, and pointer states.
- Numerical comparison shows differences and similarities among various quantum correlation measures.

## Abstract

We demonstrate a generalization of quantum discord using a generalized definition of von-Neumann entropy, which is Sharma-Mittal entropy; and the new definition of discord is called Sharma-Mittal quantum discord. Its analytic expressions are worked out for two qubit quantum states as well as Werner, isotropic, and pointer states as special cases. The R{\'e}nyi, Tsallis, and von-Neumann entropy based quantum discords can be expressed as limiting cases for of Sharma-Mittal quantum discord. We also numerically compare all these discords and entanglement negativity.