We are happy to announce our next seminar.
Speaker: Michele Notarnicola (University of Milan, ITA)
When: Thursday, 27th October 2022, 9:30 AM (CEST)
Where: Auletta QOpt – LITA 5th floor
Title: Phase-sensitive amplification for quantum loss-tolerant measurements
Abstract: Homodyne measurement is a corner-stone method of quantum optics that measures the quadratures of light, i.e. the quantum optical analog of the canonical position and momentum. However, standard homodyne is fragile to detection losses, especially in the presence of non-classical states of radiation. We propose a robust method to implement homodyne detection that is loss-tolerant, by employing optical parametric amplification to reconstruct quadrature distributions from photon-number distributions measured via direct detection. As a proof of principle, we have employed this parametric homodyne detection (PHD) setup to Wigner function tomography of a multi-mode squeezed vacuum state. The obtained Wigner function has shown a squeezing of −7.5 ± 0.4 dB and a purity of 0.91 ± 0.09 despite more than 90% detection losses. This method is suitable for the tomography of spatially and temporally multimode quantum states, proving it to be a powerful tool for optical quantum information.