Metrology and Metastability in Quantum Input-Output Systems
Explore a 44-minute lecture on metrology and metastability in quantum input-output systems presented by Madalin Guta from the University of Nottingham at the Institut Henri Poincaré. Delve into the challenges of estimating unknown parameters with high accuracy in quantum metrology and quantum control, focusing on open systems dynamics within the input-output formalism. Examine the absolute precision limit given by the quantum Fisher information and its linear scaling in the long time limit for ergodic dynamics. Investigate systems exhibiting metastability or dynamical phase transitions, where quadratic scaling occurs for times around the coherence time. Learn about the limitations of standard measurements like photon counting, homodyne, and heterodyne in achieving the quantum Fisher information. Discover preliminary research on designing measurement techniques that approach the absolute limit, with a focus on 'quantum output post-processing' using series product.