Relationship between low-temperature boson heat capacity peak and high-temperature shear modulus relaxation in a metallic glass

Low-temperature (2 K < T < 350 K) heat capacity and room-temperature shear modulus measurements (nu=1.4 MHz) have been performed on bulk Pd(41.25)Cu(41.25)P(17.5) in the initial glassy, relaxed glassy, and crystallized states. It has been found that the height of the low-temperature Boson heat capacity peak strongly correlates with the changes in the shear modulus upon high-temperature annealing. It is this behavior that was earlier predicted by the interstitialcy theory, according to which dumbbell interstitialcy defects are responsible for a number of thermodynamic and kinetic properties of crystalline, (supercooled) liquid, and solid glassy states.