Yu H B, Tylinski M, Guiseppi-Elie A, Ediger M D, Richert R
Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287, USA.
Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Phys Rev Lett. 2015 Oct 30;115(18):185501. doi: 10.1103/PhysRevLett.115.185501. Epub 2015 Oct 26.
Glassy materials display numerous important properties which relate to the presence and intensity of the secondary (β) relaxations that dominate the dynamics below the glass transition temperature. However, experimental protocols such as annealing allow little control over the β relaxation for most glasses. Here we report on the β relaxation of toluene in highly stable glasses prepared by physical vapor deposition. At conditions that generate the highest kinetic stability, about 70% of the β relaxation intensity is suppressed, indicating the proximity of this state to the long-sought "ideal glass." While preparing such a state via deposition takes less than an hour, it would require ~3500 years of annealing an ordinary glass to obtain similarly suppressed dynamics.
玻璃态材料展现出许多重要特性，这些特性与二级（β）弛豫的存在及强度相关，二级弛豫在玻璃化转变温度以下主导着动力学过程。然而，对于大多数玻璃而言，诸如退火之类的实验方案对β弛豫几乎没有什么控制能力。在此，我们报告通过物理气相沉积制备的高度稳定玻璃中甲苯的β弛豫情况。在产生最高动力学稳定性的条件下，约70%的β弛豫强度受到抑制，这表明此状态接近长期以来所寻求的“理想玻璃”。虽然通过沉积制备这样一种状态耗时不到一小时，但要使普通玻璃通过退火达到类似的动力学抑制程度则需要约3500年。
