Light scattering study of low-energy vibrational excitations in the metallic glass Ni$_{67}$Zr$_{33}$ using electronic Raman scattering

摘要

The Raman response of the metallic glass Ni$_{67}$Zr$_{33}$ is measured as afunction of polarization and temperature and analyzed theoretically.Unexpectedly, the intensity in the range up to 300\wn increases upon cooling,which is counterintuitive when the response originates from vibrations alone asin insulators. The increase finds a natural explanation if the conductionelectrons are assumed to scatter on localized vibrations with a scatteringprobability proportional to the Debye-Waller factor. None of our assumptions ismaterial specific, and the results are expected to be relevant for disorderedsystems in general.