Quantum Information Approach to Correlations in Many-body Systems

2022-9-21
Aksak, Çağan
Quantum correlations are crucial features in both quantum information theory and many-body physics. Characterization and quantification of quantum correlations have delivered a rich body of work and helped to understand some quantum phenomena. Entanglement is a unique quantum correlation for which it is a resource in many quantum information tasks. Developed for quantification of entanglement, entanglement witness formalism is a remarkable tool in the quantum information toolkit. It can be deployed beyond the entanglement theory to quantify quantum correlations in many-body systems. For many-body systems, the particle statistics and indistinguishability are essential. The relation between indistinguishability and entanglement has to be studied carefully. In this thesis, first, a class of witness operators for pairing correlations in both fermionic and bosonic systems have been proposed and the necessary and sufficient conditions for being a witness operator are found. Then, a Clauser-Horne-Shimony-Holt type test and its bounds for fermions have been demonstrated.

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Citation Formats
Ç. Aksak, “Quantum Information Approach to Correlations in Many-body Systems,” Ph.D. - Doctoral Program, Middle East Technical University, 2022.