High temperature quantum effect recorded by measuring the temperature-dependent material dispersion of silica glass

The reflection and refraction, as well as material dispersion are basic optical phenomena. The laws of reflection and refraction represent the results of the momentum conservation, depending entirely on the specific wave nature of electromagnetic fields on an interface. However, material dispersion is a consequence of interaction of light with matter. The refractive index and material dispersion are determined by the plasma and resonance frequencies, which are the functions of temperature. These characters lead to the temperature-dependent refractive index and material dispersion. When an electromagnetic wave propagates through a dielectric medium, the motions of the charged particles are affected by the incident harmonic wave and thermal radiations of random phases. The plasma and resonance frequencies are related to the thermal oscillation frequency of atoms. Consequently, the change of refractive index with temperature is proportional to the specific heat capacity. A high-temperature quantum effect is recorded by measuring the temperature-dependent material dispersion of silica glass. The number of the vibration modes per molecule varies stepwise with temperature. Because of the sluggish transition, the microcrystalline structures coexist in the glass. The detected quantum effect is related to the transitions between the “frozen-in” microcrystalline phases in glassy matrix.