We present the latest results on the experimental generation of the position and momentum (x-p) entanglement for bright optical beams as proposed by Hsu et al. [1]. Spatial entanglement is a direct test of the proposal by Einstein, Podolsky and Rosen (EPR), using beam momentum and position, which to the best of our knowledge has never been demonstrated with light. The scheme for generating spatial entanglement is based on the concept of position squeezed beams, first introduced in ref. [2], where the mode corresponding to the first derivative of the mean field has to be squeezed. In the case of a TEM{sub}00 carrier, which defines the position of the beam, this corresponds to the squeezed TEM{sub}10 mode. In particular the real and imaginary parts of the TEM{sub}10 mode represent changes in transverse position, δd, and tilt, δθ, of a TEM{sub}00 carrier beam. Only the TEM{sub}10 mode is occupied by a vacuum squeezed mode whereas all the other modes are occupied by vacuum fluctuations. The position squeezed beams are generated by a lossless combination of a vacuum amplitude squeezed TEM{sub}10 beam with a coherent TEM{sub}00 carrier beam in a Mach-Zehnder interferometer (MZI). We demonstrate measurements of the quantum correlations in the TEM{sub}10 mode with two optical parametric amplifiers. We produce stable locked squeezing at -2.5 dB below the quantum noise limit (QNL) at the detection frequency 5 MHz, as shown in Fig. 1. The measurements of the squeezing spectra show that mixing the TEM{sub}10 squeezed beam with the TEM{sub}00 carrier beam in the MZI has no influence on the amount of squeezing. The only difference is equal increase in noise power of all the traces due to the noise of the carrier beam. This proves that the x-p entanglement using the position squeezed beams is possible.
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