Properties of polyamorphousCe75Al25metallic glasses

Abstract

The thermal stability and electronic transport properties of polyamorphous ${\text{Ce}}_{75}{\text{Al}}_{25}$ metallic glass (MG) have been investigated using in situ high-pressure, high-temperature, energy-dispersive synchrotron x-ray diffraction and in situ high-pressure and low-temperature, four-probe resistance measurements. The results are compared with the properties of ${\text{La}}_{75}{\text{Al}}_{25}$ MG. The pressure dependence of the crystallization temperature and resistance of the ${\text{Ce}}_{75}{\text{Al}}_{25}$ MG exhibited turning points at the polyamorphic transition pressure, 1.5 GPa, and they clearly presented different behaviors below and above 1.5 GPa. In contrast, no turning points were observed in the ${\text{La}}_{75}{\text{Al}}_{25}$ MG (La has no $4f$ electron). Additionally, the pressure-tuned temperature coefficient of resistance of the ${\text{Ce}}_{75}{\text{Al}}_{25}$ MG was observed. These results revealed switchable properties in the polyamorphous ${\text{Ce}}_{75}{\text{Al}}_{25}$ MG that are linked with $4f$ electron delocalization.