Intuitive reason for the usefulness of entanglement in quantum metrology
Lorenzo Maccone · Physical Review A · 2013
We give a simple intuition for why and when entanglement is needed for quantum-enhanced precision measurements, and which type of entanglement is useful. We give a simple construction that shows how entanglement transforms parallel estimation strategies into sequential ones of the same precision. We employ this argument to provide some useful results and to rederive in a simpler form some known results.