Rostock 2019 – wissenschaftliches Programm
AKjDPG 3.1: Tutorium
Sonntag, 10. März 2019, 16:00–17:00, U HS 323
Quantum metrology from a quantum information science perspective — •Geza Toth1,2,3 and Iagoba Apellaniz1 — 1Theoretical Physics, University of the Basque Country UPV/EHU, E-48080 Bilbao, Spain — 2IKERBASQUE, Basque Foundation for Science, E-48011 Bilbao, Spain — 3Wigner Research Centre for Physics, H-1525 Budapest, Hungary
We discuss how quantum systems can be used for parameter estimation. We present the central notions of the field such as the quantum Fisher information and the Cramér-Rao bound. We review basic findings on how the precision of the parameter estimation scales with the number of particles in a linear interferometer. The best scaling achievable is quadratic, however, quantum entanglement is needed to surpass the linear or shot-noise scaling. Finally, we explain how uncorrelated noise limits the highest achievable precision in practice. We present the theory of quantum metrology based on concrete setups using highly entangled quantum states, such as Greenberger-Horne-Zeilinger states, spin squeezed states, Dicke states and singlet states.