Condensed Matter and Surface Sci. Prog., Dept. of Phys., Ohio Univ., Athens, OH 45701
Inst. de Fisica, UNAM, Mexico D. F., Mexico
The elastic properties of randomly disordered multilayered systems that are periodic on average are studied. Specifically, a layered structure is considered that is made up of two different materials with elastic waves propagating perpendicular to the interfaces. The localization length for frequencies of the propagating waves around the band gaps in the dispersion relation of the average periodic system are computed. Two types of disorder are considered. In one case the specific acoustic impedance of each slab in the structure is kept constant while randomly varying the thicknesses of the slabs. In the second case the period of the structure is kept constant while randomly varying the specific acoustic impedance of the layers. The effects of dissipation on the localization length are also studied.