Observation of Time-Dependent Specific Heat in Amorphous SiO2

Abstract
The time-dependent specific heat of amorphous SiO2 has been measured between 0.1 and 1 K over the range ∼ 1 sec to 10 μsec. The decoupling of the roughly T-dependent contribution to specific heat is observed in submillisecond time scales, in qualitative agreement with the predictions of the tunneling model. However, the excess T3-dependent specific heat is not decoupled on the time scales involved.