The glass transition of a molecular glass former is monitored by means of measurements of the spin relaxation rates of implanted muons. The data measured under transverse fields upon heating the material from the glass phase are consistent with the onset of ergodicity-restoring motions some 22 K above the calorimetric glass transition. The results show that the technique can be fruitfully exploited to assess the presence of criticality within the supercooled liquid at microsecond scales.

• Received 30 October 2002

DOI:https://doi.org/10.1103/PhysRevB.67.184201