Time-resolved homodyne characterization of individual quadrature-entangled pulses
Laboratoire Charles Fabry de l'Institut d'Optique, CNRS
UMR 8501, 91403 Orsay, France
Corresponding author: a firstname.lastname@example.org
Published online: 21 December 2004
We describe a simple and efficient set-up to generate and characterize femtosecond quadrature-entangled pulses. Quantum correlations equivalent to about 2.5 dB squeezing are efficiently and easily reached using the non-degenerate parametric amplification of femtosecond pulses through a single-pass in a thin (100 μm) potassium niobate crystal. The entangled pulses are then individually sampled to characterize the non-separability and the entropy of formation of the states. The complete experiment is analysed in the time-domain, from the pulsed source of quadrature entanglement to the time-resolved homodyne detection. This particularity allows for applications in quantum communication protocols using continuous-variable entanglement.
PACS: 42.50.Dv – Nonclassical states of the electromagnetic field, including entangled photon states; quantum state engineering and measurements / 03.67.-a – Quantum information / 03.65.Wj – State reconstruction, quantum tomography
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005