ESR study of glass transition in Mn-doped Se70Te30 chalcogenide glass in non-isothermal process

The ESR measurements of manganese ions in Se70Te30 chalcogenide glass have been carried out during rate-scan heating in order to investigate the glass transition phenomena. ESR signals observed at various measuring temperatures during rate-scan heating are centered at g = 2.00 with no hyperfine structure. No remarkable change in the peak-to-peak linewidth occurs from room temperature up to the glass transition temperature, but the linewidth begins to decrease around the glass transition temperature and to increase above the crystallization temperature. When the maximum temperature in the rate-scan heating is above the glass transition but below the crystallization temperature, the ESR linewidth retraces almost the same curve in the cooling to room temperature. This line narrowing above the glass transition temperature may be regarded as motional narrowing occurring in the supercooled liquid state.