Light scattering study of low-energy vibrational excitations in the metallic glass Ni67Zr33using electronic Raman scattering

Abstract

The Raman response of the metallic glass Ni67Zr33 is measured as a function of polarization and temperature and analyzed theoretically. Unexpectedly, the intensity in the range up to 300 cm −1 increases upon cooling, which is counterintuitive when the response originates from vibrations alone as in insulators. The increase finds a natural explanation if the conduction electrons are assumed to scatter on localized vibrations with a scattering probability proportional to the Debye-Waller factor. None of our assumptions is material specific, and the results are expected to be relevant for disordered systems in general.