HIGH-RESOLUTION OPTICAL SPECTROSCOPY OF LANGMUIR-BLODGETT-FILMS

High-resolution spectroscopy of disordered solids is briefly reviewed. The hole-burning method is applied to an amphiphilic cyanine in Langmuir Blodgett (LB) mono- and multilayers. The hole width probes low-temperature motion in the LB film. In particular, the outermost (surface) layer is found to bear specific low-energy dynamics attributed to chain motion. Spectral holes are also used as probes of external perturbations such as immersion in liquid helium and application of a static electric field. The latter effect allows us to evaluate the orientation and direction of the molecular axes.