Brunner Matthias, Bechinger Clemens
Physics Department, University of Konstanz, D-78457 Konstanz, Germany.
Phys Rev Lett. 2002 Jun 17;88(24):248302. doi: 10.1103/PhysRevLett.88.248302. Epub 2002 May 31.
We investigate the melting process of a two-dimensional charge-stabilized colloidal system in the presence of a triangular substrate potential. This potential is formed by an optical interference pattern that allows the substrate strength to be varied continuously. By means of an additional scanned optical tweezer the particle density can be adjusted to different numbers m of colloidal particles per substrate minima; here we concentrate on the case of trimers, i.e., m = 3. Because trimers exhibit additional internal degrees of rotational freedom, the phase behavior of such a system is very different from homogeneous or one-dimensional periodic substrate potentials.
我们研究了在三角形衬底势存在的情况下二维电荷稳定胶体系统的熔化过程。这种势由光学干涉图案形成，使得衬底强度能够连续变化。借助额外的扫描光镊，可以将粒子密度调整为每个衬底极小值处不同数量(m)的胶体粒子；这里我们专注于三聚体的情况，即(m = 3)。由于三聚体表现出额外的内部旋转自由度，这样一个系统的相行为与均匀或一维周期性衬底势有很大不同。
