Harden J L, Mackintosh F C, Olmsted P D
Department of Chemical Engineering, Johns Hopkins University, Baltimore, Maryland 21218-2689, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2005 Jul;72(1 Pt 1):011903. doi: 10.1103/PhysRevE.72.011903. Epub 2005 Jul 5.
We study the stability and shapes of domains with spontaneous curvature in fluid films and membranes, embedded in a surrounding membrane with zero spontaneous curvature. These domains can result from the inclusion of an impurity in a fluid membrane or from phase separation within the membrane. We show that for small but finite line and surface tensions and for finite spontaneous curvatures, an equilibrium phase of protruding circular domains is obtained at low impurity concentrations. At higher concentrations, we predict a transition from circular domains, or caplets, to stripes. In both cases, we calculate the shapes of these domains within the Monge representation for the membrane shape. With increasing line tension, we show numerically that there is a budding transformation from stable protruding circular domains to spherical buds. We calculate the full phase diagram and demonstrate two triple points of, respectively, bud-flat-caplet and flat-stripe-caplet coexistence.
我们研究了嵌入具有零自发曲率的周围膜中的流体膜和膜中具有自发曲率的区域的稳定性和形状。这些区域可能源于流体膜中杂质的包含或膜内的相分离。我们表明，对于小但有限的线张力和表面张力以及有限的自发曲率，在低杂质浓度下可获得突出圆形区域的平衡相。在较高浓度下，我们预测会从圆形区域或小帽状区域转变为条纹状区域。在这两种情况下，我们都在膜形状的蒙日表示法中计算这些区域的形状。随着线张力的增加，我们通过数值计算表明存在从稳定的突出圆形区域到球形芽的出芽转变。我们计算了完整的相图，并展示了分别为芽 - 平 - 小帽状和平 - 条纹 - 小帽状共存的两个三相点。
