Generalized concurrence and limits of separability for two qutrits

TL;DR

This paper extends the concept of concurrence to two qutrits, providing a method to measure entanglement and bounds on separability, with comparisons to negativity.

Contribution

It introduces a generalized concurrence for two qutrits that aligns with Wootters' measure for qubits and offers bounds on separability for symmetric states.

Findings

Extended concurrence matches Wootters for qubits

Computed bounds on separability for symmetric states

Compared concurrence with negativity

Abstract

We present an extension of the Wootters concurrence for the case of two qutrits in mixed states. The reduction of our extension to the case of two levels shows complete agreement with Wootters concurrence for two qubits. As an explicit example, we compute the concurrence for a family of symmetric states and we obtain the bounds on the limit for separability. Our results are compared with those of the negativity.