2005/11/28 by A. S. Gittings, D. J. Durian
Chemistry · Physics and Astronomy · #Beam (structure) #Computational physics #Electric field #Gaussian #Gaussian beam #Materials science #Optics #Physics #Plane wave #Random lasers and scattering media #Speckle pattern #Spectroscopy #Spectroscopy and Laser Applications #Spectroscopy and Quantum Chemical Studies #cond-mat.soft
paper · pdf · doi:10.1364/ao.45.002199
published as Appl. Opt. 45, 2199-2204 (2006) · experiment, available at http://www.opticsinfobase.org/abstract.cfm?URI=ao-45-10-2199
arxiv created 2005/11/28 · openalex publication_date 2006/04/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
All previous applications of diffusing-wave spectroscopy to aqueous foams have relied on the assumption that the electric field of the detected light is a Gaussian random variable and hence that the Siegert relation applies. We test this crucial assumption by simultaneous measurement of both second- and third-order temporal intensity correlations. We find that the electric field is Gaussian for typical experimental geometries equivalent to illumination and detection with a plane wave, both for backscattering and transmission through an optically thick slab. However, we find that the Gaussian character breaks down for point-in-point-out backscattering geometries in which the illumination spot size is not sufficiently large in comparison with the size of the intermittent rearrangement events.