Collective excitations in Ni62Nb38 glass from partial scattering functions

Propagating vibrational modes in the Zr–Be metallic glasses

“…We notice that the positions of the low-energy peak, as derived from the J l (Q, E) representation of the spectra, oscillate as a function of momentum transfer around the average band energy of ∼16 meV. The two minima visible in the experimental range closely correspond to the positions of the maxima in the static structure factor (figure 4) similarly to earlier observations at Q p (position A) in the other metallic glasses (Mg 70 Zn 30 [1], Ni 67 Zr 33 [3], Ni 62 Nb 38 [4]). Such behavior of the low-energy excitations closely resembles acoustic phonon branches in ordered crystals and permits us to identify this band as an 'acoustic-like' mode involving predominantly Zr-Zr bonds.…”

“…Recently we have carried out measurements of the inelastic neutron scattering intensities I (E, ) in binary alloys Ni 62 Nb 38 [4]. The isotopes 58 Ni, 60 Ni and 58/64 Ni with different scattering cross-sections were used for preparation of the samples.…”

Observation of the collective vibrational modes in Ni42Nb58 metallic glass

“…Perhaps, that the excitations of order 30 meV are an optic-phonon like mode as in the case of a two-component crystal. The similar results also have been obtained for Ni 62 Nb 38 sample [6]. Apart from that the low energy ($7 meV) mode has been observed in Ni 62 Nb 38 sample.…”

“…The aim of this whole project is to understand nature of the propagating vibration modes at the level of partial functions. Recently we have carried out the measurements of the dynamic structure factors in Ni 62 Nb 38 using isotope substituted samples [6]. Three types of vibrational modes (low-energy $7 meV, middle-energy 15-22 meV and high-energy $32 meV) were observed.…”

Force constant disorder in the Ni44Nb56 bulk metallic glass as observed by deep inelastic neutron scattering augmented by isotopic substitution

“…Due to the existence of isotopic mass, positional, and force-constant disorder, probes of local structure and dynamics are prone to be more successful in studying BMG properties. Numerous local structural probes have been applied [36][37][38][39][40][41], but the experimental techniques that have been employed so far to elucidate the local dynamics of disordered systems such as BMGs have been limited to inelastic neutron scattering [42][43][44][45][46][47][48]. One of the new promising techniques for probing local dynamics that can be successfully applied to investigations of disordered systems is deep inelastic neutron scattering (DINS).…”