Differential evolution for many-particle adaptive quantum metrology

Phys Rev Lett. 2013 May 31;110(22):220501. doi: 10.1103/PhysRevLett.110.220501. Epub 2013 May 28.

Abstract

We devise powerful algorithms based on differential evolution for adaptive many-particle quantum metrology. Our new approach delivers adaptive quantum metrology policies for feedback control that are orders-of-magnitude more efficient and surpass the few-dozen-particle limitation arising in methods based on particle-swarm optimization. We apply our method to the binary-decision-tree model for quantum-enhanced phase estimation as well as to a new problem: a decision tree for adaptive estimation of the unknown bias of a quantum coin in a quantum walk and show how this latter case can be realized experimentally.