Low-Frequency Vibrations of Soft Colloidal Glasses
Low-Frequency Vibrations of Soft Colloidal Glasses
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DOI：
10.1103/physrevlett.105.025501
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发表时间：
2010-07-09
影响因子：
8.6
通讯作者：
Yodh, A. G.
中科院分区：
文献类型：
--
作者：
Chen, Ke;Ellenbroek, Wouter G.;Yodh, A. G.
我们对胶体热敏水凝胶颗粒的二维填充进行了实验，其填充分数可以通过改变温度来调节到堵塞转变以上。通过测量粒子之间的位移关联，我们提取了具有相同构型和相互作用、但粒子的动力学未受抑制的相应“阴影”系统的振动特性。振动特性与原子和分子玻璃中的零温度球填充的预测非常相似；在低频有一个玻色子峰值，当系统压缩到干扰跃迁上方时，该峰值移动到更高的频率。
We conduct experiments on two-dimensional packings of colloidal thermosensitive hydrogel particles whose packing fraction can be tuned above the jamming transition by varying the temperature. By measuring displacement correlations between particles, we extract the vibrational properties of a corresponding "shadow'' system with the same configuration and interactions, but for which the dynamics of the particles are undamped. The vibrational properties are very similar to those predicted for zero-temperature sphere packings and found in atomic and molecular glasses; there is a boson peak at low frequency that shifts to higher frequency as the system is compressed above the jamming transition.