Quantum Entanglement with Geometric Measures

TL;DR

This paper develops new geometric measure-based tools and algorithms for quantifying high-dimensional quantum entanglement across various system types, enhancing both theoretical understanding and practical computation.

Contribution

It introduces a unified framework of GME-based entanglement monotones for diverse quantum states and develops optimization methods for their efficient computation.

Findings

Effective detection of high-dimensional entanglement.

Unified approach for bipartite and multipartite systems.

Robust bounds via semidefinite programming.

Abstract

Quantifying quantum entanglement is a pivotal challenge in quantum information science, particularly for high-dimensional systems, due to its computational complexity. This thesis extends the geometric measure of entanglement (GME) to introduce and investigate a suite of GME-based entanglement monotones tailored for diverse quantum contexts, including pure states, subspaces, and mixed states. These monotones are applicable to both bipartite and multipartite systems, offering a unified framework for characterizing entanglement across various scenarios. Notably, the proposed monotones are adept at identifying entanglement with varying entanglement dimensionalities, making them particularly effective for detecting high-dimensional entanglement. To support practical computation, we develop a non-convex optimization framework that yields accurate upper bounds, complemented by semidefinite programming techniques to establish robust lower bounds. Together, these approaches provide a consistent and efficient computational methodology. This work advances both the theoretical understanding and algorithmic tools for entanglement quantification, contributing to the study of complex quantum correlations in entangled systems.