Phys Rev E Stat Nonlin Soft Matter Phys. 2001 Jun;63(6):061404. doi: 10.1103/PhysRevE.63.061404. Epub 2001 May 23.

Diffusing-wave spectroscopy of nonergodic media.

Physical review. E, Statistical, nonlinear, and soft matter physics

F Scheffold, S E Skipetrov, S Romer, P Schurtenberger

PMID: 11415101 DOI: 10.1103/PhysRevE.63.061404

Abstract

We introduce an elegant method that allows the application of diffusing-wave spectroscopy (DWS) to nonergodic, solidlike samples. The method is based on the idea that light transmitted through a sandwich of two turbid cells can be considered ergodic even though only the second cell is ergodic. If absorption and/or leakage of light take place at the interface between the cells, we establish a so-called "multiplication rule," which relates the intensity autocorrelation function of light transmitted through the double-cell sandwich to the autocorrelation functions of individual cells by a simple multiplication. To test the proposed method, we perform a series of DWS experiments using colloidal gels as model nonergodic media. Our experimental data are consistent with the theoretical predictions, allowing quantitative characterization of nonergodic media and demonstrating the validity of the proposed technique.

Publication Types

• Journal Article