主講人：John Charles Mcintosh Gray
主題：Tensor Network Tomography
Dr. John Gray is a post-doc at Imperial College London currently studying mostly digital quantum simulation for many-body systems. He recently received his PhD from University College London where he worked (with Prof. Abolfazl Bayat) on a range of topics including many-body localization and how to both measure and compute many-body entanglement measures. He has a particular interest in tensor networks and maintain two open-source libraries, 'quimb' and 'opt_einsum', that deal with manipulating and contracting tensor networks.
In the NISQ era of quantum devices, verification and characterization of operation is a key task. Tomography would be the ultimate tool here but is currently impractical for more than a few qubits. We investigate using tensor networks - one of the state-of-the-art methods in terms of classically representing quantum states - to make tomography both more flexible and efficient. We apply the method to IBMQ devices to quantify the genuine entanglement generated during random circuit evolutions, in doing so benchmarking their performance.