Entanglement measures

Entanglement is considered to be physical resource in quantum information theoretic protocols, including quantum teleportation, super-dense coding, quantum cryptography, and measurement-based quantum computation. Entanglement theory have also been applied in probing gauge-gravity duality, in understanding time as an emergent phenomena, and in studying photo-synthetic complexes. Quantum many-body systems have emerged as the natural choice for implementing quantum information processing tasks, and for testing concepts developed in entanglement theory.

For nearly three decades, quantifying entanglement has been extensively studied and has been found to be generally difficult, specially in a way which is experimentally relizable even without having full knowledge of the states. While substantial theoretical as well as experimental advancements in detecting and measuring entanglement have been achieved in a bipartite scenario, quantifying entanglement in multipartite domain still remains a challenging task. Our current research is directed towards investigating how to quantify multiparty entanglement over arbitrary subsystems in a quantum many-body system, assisted by local measurements on the rest of the system.