Rostock 2019 – scientific programme

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AKjDPG: Arbeitskreis junge DPG

AKjDPG 3: Tutorial Quantum Metrology

AKjDPG 3.1: Tutorial

Sunday, March 10, 2019, 16:00–17:00, U HS 323

Quantum metrology from a quantum information science perspective — •Geza Toth^1,2,3 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.