Eur. Phys. J. Special Topics 199, 167-180 (2011)
https://doi.org/10.1140/epjst/e2011-01512-2

Regular Article

Photon path length distribution in random media from spectral speckle intensity correlations

¹ Departamento de Física, Cinvestav-IPN, Av. Instituto Politécnico Nacional 2508, 07360 México D.F., México
² Dipartimento di Fisica e Matematica, Università degli Studi dell’Insubria, via Valleggio 11, 22100 Como, Italy
³ Dipartimento di Fisica, Università degli studi di Milano, via Celoria 16, 20133 Milano, Italy
⁴ Department of Physics and Fribourg Center for Nanomaterials, University of Fribourg, 1700 Fribourg, Switzerland

^a e-mail: frank.scheffold@unifr.ch

Received: 29 August 2011
Revised: 4 October 2011
Published online: 7 December 2011

Abstract

We show that the spectral speckle intensity correlation (SSIC) technique can be profitably exploited to recover the path length distribution of photons scattered in a random turbid medium. We applied SSIC to the study of Teflon slabs of different thicknesses and were able to recover, via the use of the photon diffusion approximation theory, the characteristic transport mean free path ℓ^∗ and absorption length s_a of the medium. These results were compared and validated by means of complementary measurements performed on the same samples with standard pulsed laser time of flight techniques.