Theoretical Tools for Quantum Sensor Optimization and Entanglement Quantification

Abstract: 

In this work, we develop theoretical tools aimed at facilitating more useful quantum sensors and more efficient methods of entanglement quantification. First, we discuss a quantum-classical algorithm for estimating the quantum Fisher information- a canonical quantity in quantum metrology. Then, we turn to the study of multipartite entanglement using minimal resources. We introduce a general family of multipartite entanglement before constructing statistical estimators for these measures that utilize only measurements which are implementable using today’s technologies. Finally, we provide rigorous performance guarantees and a summary the practical tradeoffs among our estimators.