Abstract
We present an overview of the modern study of soft matters from the point of view of condensed matter physics. The common feature of a soft matter is the presence of a mesoscopic length scale which necessarily plays a key role in determining properties of the system. As an example of a soft matter, we consider a microemulsion which consists of water, oil, and surfactant. Microemulsions are known to be thermodynamically stable, and show rich phase behaviors. The importance of phenomenological approaches to such a complex system is stressed by explaining lattice spin models, Ginzburg-Landau theories, and membrane curvature elasticity theories. All of these theories are successful in understanding the basic properties of microemulsions. Finally, recent experimental and theoretical findings on polymeric microemulsions are briefly reviewed.
