Pulsed homodyne Gaussian quantum tomography with low detection efficiency
Martina Esposito, Fabio Benatti, Roberto Floreanini, Stefano Olivares, Francesco Randi, Kelvin Titimbo, Micol Pividori, Fabio Novelli, Federico Cilento, F. Parmigiani, Daniele Fausti · 2024
Pulsed homodyne quantum tomography usually requires a high detection efficiency, limiting its applicability in quantum optics. Here, it is shown that the presence of low detection efficiency (<50%) does not prevent the tomographic reconstruction of quantum states of light, specifically, of Gaussian states. This result is obtained by applying the so-called minimax adaptive reconstruction of the Wigner function to pulsed homodyne detection. In particular, we prove, by both numerical and real experiments, that an effective discrimination of different Gaussian quantum states can be achieved. Our finding paves the way to a more extensive use of quantum tomographic methods, even in physical situations in which high detection efficiency is unattainable.