Homodyne measurement of exponential phase moments for quantum-phase reconstruction
نویسندگان
چکیده
We directly sample the exponential moments of the canonical phase for various quantum states from the homodyne output. The method enables us to study the phase properties experimentally, without making the detour via reconstructing the density matrix or the Wigner function and calculating the phase statistics from them. In particular, combing the measurement with a measurement of the photon-number variance, we verify fundamental number–phase uncertainty.
منابع مشابه
Exponential Moments of Canonical Phase: Homodyne Measurements
A method for direct sampling of the exponential moments of canonical phase from the data recorded in balanced homodyne detection is presented. Analytical expressions for the sampling functions are shown which are valid for arbitrary states. A numerical simulation illustrates the applicability of the method and compares it with the direct measurement of phase by means of double homodyning.
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