An explicit formula is given for the quantity of entanglement in the output state of a beam splitter, given the squeezed vacuum states input in each mode.
@article{arxiv.quant-ph/0204082,
title = {Properties of a beam splitter entangler with Gaussian input states},
author = {Wang Xiang-bin},
journal= {arXiv preprint arXiv:quant-ph/0204082},
year = {2009}
}