New Approaches of Laser Light Scattering Spectroscopy

Abstract

A spectroscopic technique with high sensitivity and spatial resolution is crucial for the analyses of liquids in nano-spaces and at interfacial areas. Especially, new techniques have been desired that can be applied to analyses of the dynamic behavior of molecular assemblies in buried restricted environments, such as at oil/water interfaces and in living cells. Here, we present our new experimental techniques, namely "Time-Resolved Quasi Elastic Laser Scattering" and "Electron Enhanced Raman Scattering", which are expected to meet such requirements. We show various investigations on the structures of liquids and the dynamic behaviors of molecular assemblies under restricted geometries with these new techniques.

Analysis of a Quasi-Elastic Laser Scattering Spectrum Using the Maximum Entropy Method

“…Many researchers have reported that the QELS method is appropriate for surface tension measurements, indicating that the surface tensions calculated from the capillary wave frequencies agreed with the other methods. [2][3][4][5][6][7][8] We fabricated a conventional laser heterodyne QELS measurement system using a diffraction grating as a local oscillator, and have reported on the dynamics of the mass transfer of surfactants at a liquid/liquid interface. [9][10][11][12][13] Furthermore, we devised a new principle of the QELS method using a monoluminous flux detection technique in a beam divergence, and have achieved 50 -100 times higher S/N ratios than the conventional heterodyne system.…”