Universal dynamics behavior in superionic conducting glasses

Abstract

The inelastic neutron scattering experiment on superionic glass system AgI-AgPO 3 have been performed in the energy and momentum transfer range from − 5 to 15 meV and 0 to 8 Å − 1 , respectively by using a time of flight MARI instrument at Rutherford Appleton Laboratory, ISIS, UK. The E-dependence of the inelastic data show an excess intensity at low energy around 3 meV, the so-called Boson peak, which increased with the dopant salt. The Q-dependence of the elastic scattering reveals a prepeak at anomalously low Q value around 0.8 Å − 1 , which is not observed in the undoped AgPO 3 glass. The Q-dependence in the energy region from 1 to 3 meV shows clearly an excess intensity at Q ~ 2.2 Å − 1 compared with the undoped AgPO 3. All these features correlate with the increasing mobility of Ag + ions due to the expansion of the network structure caused by salt doping, which leads to the increase of ionic conductivity. Similar results have also been observed in the corresponding superionic glass system AgI-Ag 2S-AgPO 3 that was observed by both MARI and NEAT instrument at HMI, Berlin. The results show a universal dynamic behavior in silver phosphate glasses.