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Phase Sensitivity of a Mach-Zehnder Interferometer

Luca Pezze'·Augusto Smerzi
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Abstract

The best performance of a Mach-Zehnder interferometer is achieved with the input state |N_T/2 + 1>|N_T/2-1 > + |N_T/2 - 1>|N_T/2+1>, being N_T the total number of atoms/photons. This gives: i) a phase-shift error confidence C_{68%}=2.67/N_T with ii) a single interferometric measurement. Different input quantum states can achieve the Heisenberg scaling ~ 1/N_T but with higher prefactors and at the price of a statistical analysis of two or more independent measurements.

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Luca Pezze', Augusto Smerzi. 2005-11-07. Phase Sensitivity of a Mach-Zehnder Interferometer. https://doi.org/10.1103/physreva.73.011801

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