How focused pumping affects type-II spontaneous parametric down-conversion
P. S. K. Lee, Martin P. Van Exter, J. P. Woerdman · Physical Review A · 2005
We demonstrate that the transition from plane-wave to focused pumping in type-II down-conversion is analogous to the transition from cw to pulsed pumping. We show experimentally that focused pumping leads to asymmetric broadening of both the ordinary and extraordinary light distribution. It hardly affects the entanglement quality if proper spatial filtering is applied.