Coulomb-like interaction in nematic emulsions induced by external torques exerted on the colloids.
Coulomb-like interaction in nematic emulsions induced by external torques exerted on the colloids.
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由施加在胶体上的外部扭矩引起的向列乳液中的类库仑相互作用。
DOI：
10.1103/physreve.76.011707
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
V. Uzunova
中科院分区：
文献类型：
--
作者：
V. Pergamenshchik;V. Uzunova
在浸没在双折射液晶中的胶体上的外部机械扭矩可以在它们之间诱导类似库仑的1/r相互作用[Lev和Tomchuk，Phys.Rev.E59，591（1999）; Lev，同上，65，021709（2002）]。本文证明了两种胶体的指向矢介导的类库仑相互作用是由作用在这些胶体上的横向外力矩的矢量γ垂直（1）和γ垂直（2）决定的。我们推导出1/r势，其中两个力矩的标量积-（Gamma垂直（1）x Gamma垂直（2））起着两个静电荷的乘积的作用。1/r相互作用在（Gamma垂直（1）x Gamma垂直（2））>0时是吸引的，在（Gamma垂直（1）x Gamma垂直（2））<0时是排斥的（“平行力矩”吸引，而“反平行力矩”相互排斥）。横向扭矩的矢量决定了两个分量的“弹性电荷”（二分力），这在弹性能中由1/r2和1/r3项（偶极子-偶极子和偶极子-偶极子相互作用的弹性类似物）说明。的一般状态的成对的方法，以乳化液被认为是在弹性电荷密度。
An external mechanical torque on colloids immersed in a nematic liquid crystal can induce a Coulomb-like 1/r interaction between them [Lev and Tomchuk, Phys. Rev. E 59, 591 (1999); Lev, ibid. 65, 021709 (2002)]. In this paper we show that the director-mediated Coulomb-like interaction of two colloids is determined by the vectors Gamma perpendicular (1) and Gamma perpendicular (2) of the transverse external torques exerted upon these colloids. We derive the 1/r potential in which the scalar product -(Gamma perpendicular (1) x Gamma perpendicular (2)) of the two torques plays the role of the product of two electrostatic charges. The 1/r interaction is attractive for (Gamma perpendicular (1) x Gamma perpendicular (2))>0 and repulsive for (Gamma perpendicular (1) x Gamma perpendicular (2))<0 ("parallel torques" attract whereas "antiparallel torques" repel each other). The vector of transverse torque determines the two-component "elastic charge" (dyad), which is illustrated by the 1/r2 and 1/r3 terms in the elastic energy (the elastic analogs of the monopole-dipole and dipole-dipole interactions). The general status of the pairwise approach to nematic emulsions is considered in terms of the elastic charge density.