Eur. Phys. J. D 63, 457-461 (2011)
https://doi.org/10.1140/epjd/e2011-20153-9

Regular Article

Demonstrating various quantum effects with two entangled laser beams

¹ ARC Centre of Excellence for Quantum-Atom Optics, Department of Quantum Science, The Australian National University, Canberra, Australian Capital Territory 0200, Australia
² Centre for Quantum Computation and Communication Technology, Department of Quantum Science, The Australian National University, Canberra, Australian Capital Territory 0200, Australia

^a e-mail: boris.hage@anu.edu.au

Received: 11 March 2011
Published online: 23 June 2011

Abstract

We report on the preparation of entangled two mode squeezed states of yet unseen quality. Based on a measurement of the covariance matrix we found a violation of the Reid and Drummond EPR-criterion at a value of only 0.36 ± 0.03 compared to the threshold of 1. Furthermore, quantum state tomography was used to extract a single photon Fock state solely based on homodyne detection, demonstrating the strong quantum features of this pair of laser-beams. The probability for a single photon in this ensemble measurement exceeded 2/3.