Sullivan M T, Zhao K, Hollingsworth A D, Austin R H, Russel W B, Chaikin P M
Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
Phys Rev Lett. 2006 Jan 13;96(1):015703. doi: 10.1103/PhysRevLett.96.015703. Epub 2006 Jan 9.
Particle concentration is a dominant control parameter for colloids and other soft matter systems. We demonstrate a simple technique, "dielectrophoretic equilibrium," implemented as an "electric bottle," a planar capacitor in a larger volume. The uniform field in the capacitor traps particles in this force-free region at a higher density than in the zero field regions outside. We show how the technique measures the equation of state and we initiate and grow colloidal crystals. "Dielectrophoretic equilibria" enable the study of a complete concentration-dependent phase diagram from a single microscopic sample, obviating the previous need for preparing a large number of samples.
颗粒浓度是胶体和其他软物质系统的一个主要控制参数。我们展示了一种简单的技术，即“介电泳平衡”，它被实现为一个“电瓶”，也就是一个置于较大体积空间中的平面电容器。电容器中的均匀场将颗粒捕获在这个无作用力区域，其密度高于外部的零场区域。我们展示了该技术如何测量状态方程，以及我们如何引发和生长胶体晶体。“介电泳平衡”能够从单个微观样品研究完整的浓度依赖性相图，从而无需像以前那样制备大量样品。
