High temperature vibrational dynamics in SiO2

We propose to measure the T-evolution of the vibrational density of states in SiO2, from room temperature up to the liquid state. Our main target is the comprehension of the mechanisms underlying the boson peak. To the best of our knowledge, this experiment can be done only with the RISO furnace installed on LET. In addition, by exploiting the repetition rate multiplication of LET, we will get high-resolution measurements of the dynamic structure factor to determine the non-ergodicity factors, thus improving the comprehension of the glass transition phenomenology in the prototypical system of strong glassformer.

本研究拟测量二氧化硅（SiO₂）中振动态密度（vibrational density of states）的温度演化过程，测量温区覆盖从室温至液态。本研究的核心目标为阐明玻色峰（boson peak）背后的内在物理机制。据我们所知，该实验仅可依托安装于LET的RISO炉（RISO furnace）完成。此外，通过利用LET的重复频率倍增技术，本研究将实现动态结构因子（dynamic structure factor）的高分辨测量，进而确定非遍历因子（non-ergodicity factors），从而深化对强玻璃形成体典型体系中玻璃转变现象学的理解。