2005/08/08 by Gabriel Molina‐Terriza, Gabriel Molina-Terriza, Stefano Minardi +4 · 2 citations
Physics and Astronomy · #Advanced Fiber Laser Technologies #Laser-Matter Interactions and Applications #Orbital Angular Momentum in Optics #quant-ph
paper · pdf · doi:10.1103/physreva.72.065802
arxiv created 2005/08/08 · openalex publication_date 2005/12/21 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We show experimentally how the spatial shape of the pump beam controls the ellipticity of the spatial mode function in noncollinear spontaneous parametric down-conversion. The degree of ellipticity depends on the pump beam width, especially for highly focused beams. We introduce an effective length, the so-called noncollinear length, that determines the importance of the ellipticity of the spatial mode function. We also discuss the ellipticity induced by the spectrum of the pump beam.