Interface effects and elastic constants of Ag/Ni superlattices studied by Brillouin scattering

The Brillouin light scattering technique was used to study the elastic properties and interface effects of Ag/Ni superlattices. The two effective elastic constants c11 and c44 were determined for both free-standing and glass-supported superlattices. C44 was found to decrease by 40% as the period decreased from 19 to 1.3 nanometers while c11 proved to be period-independent. Measurements on supported specimens also revealed information on the constant c33 which exhibited a monotonic increase with period. Interface quality was also seen to improve with lowered temperature.