Heralded processes on continuous-variable spaces as quantum maps

Franck Ferreyrol (1, 2) , Nicolò Spagnolo (2, 3) , Rémi Blandino (4) , Marco Barbieri (4) , Rosa Tualle-Brouri (4)

1 CQD - Centre for Quantum Dynamics
2 LCF - Laboratoire Charles Fabry
3 Dipartimento di Fisica [Roma La Sapienza]
4 Laboratoire Charles Fabry / Optique Quantique

Conditional evolution is crucial for generating non-Gaussian resources for quantum information tasks in the continuous variable scenario. However, tools are lacking for a convenient representation of heralded process in terms of quantum maps for continuous variable states, in the same way as Wigner functions are able to give a compact description of the quantum state. Here we propose and study such a representation, based on the introduction of a suitable transfer function to describe the action of a quantum operation on the Wigner function. We also reconstruct the maps of two relevant examples of conditional process, that is, noiseless amplification and photon addition, by combining experimental data and a detailed physical model. This analysis allows to fully characterize the effect of experimental imperfections in their implementations.

Domaines: Physique Quantique [quant-ph]

Franck Ferreyrol, Nicolò Spagnolo, Rémi Blandino, Marco Barbieri, Rosa Tualle-Brouri. Heralded processes on continuous-variable spaces as quantum maps. 2012. ⟨hal-00701913v1⟩