Title: SPECTRA OF TRANSVERSE EXCITATIONS IN LIQUID GLASS-FORMING METALLIC ALLOY Mg_{70}Zn_{30}: TEMPERATURE DEPENDENCE
Authors: T.Bryk (Department of Physics, University of Texas, Austin, Texas 78712, USA; Institute for Condensed Matter Physics, of the National Academy of Sciences of Ukraine, 1 Svientsitskii Str., 290011 Lviv, Ukraine), I.Mryglod (Institute for Condensed Matter Physics, of the National Academy of Sciences of Ukraine, 1 Svientsitskii Str., 290011 Lviv, Ukraine)

The temperature dependence of the dispersion and damping coefficients of transverse excitations in metallic alloy Mg$_{70}$Zn$_{30}$ at the number density $n=0.0435$\AA$^{-3}$ is studied using the method of generalized collective modes. The spectra of generalized transverse modes have been obtained within the four-variable approximation for three temperatures 1210 K, 833 K and 713 K. It is shown that the propagating gap which characterizes the crossover between hydrodynamic fluid-like and viscoelastic solid-like behaviour reduces when the temperature decreases. The generalized $k$-dependent shear viscosity $\eta(k)$ calculated within the same approximation increases rapidly at $k=0$ and its shape becomes more narrow by transition from a well-defined liquid state to an undercooled one.

Comments: Figs. 3, Refs. 16, Tabs. 0.