Exploring Quantum Correlations Beyond Entanglement: A Study of LQU and LQFI in Qubit Networks
摘要
Quantum entanglement, a specific form of quantum correlation, plays a crucial role in quantum information science, particularly in areas such as quantum computing and communication. The measurement and analysis of quantum correlations, especially in open systems subject to decoherence, present a central challenge for the implementation of quantum protocols. Beyond entanglement, other non-classical correlations like quantum discord (QD) have been extensively studied, providing alternatives for characterizing quantum interactions. Geometric measures such as local quantum uncertainty (LQU) and local quantum Fisher information (QFI) have been proposed to quantify these correlations. These measures are closely linked to the precision of quantum metrology protocols, especially in optimal phase estimation. This study explores the relationship between LQU and LQFI, offering new insights into their interaction in qubit networks.