Lattice Waves In Dusty Plasmas

During the past decade, the physics of dusty plasmas have developed into an important branch of plasma science. Charged dusts exist widely in space plasma, laboratory fusion devices and plasma assistant processing equipment. Dusty plasmas consist of electrons, ions and usually negatively charged dusty micro-particles. The study on electrostatic waves promulgating in dusty plasmas has become a focal problem. Laboratory observations of dusty plasma crystals have opened a new research area in dusty plasma physics. A dusty plasma crystal is a strongly coupled system. It is then a perfect model for studying phase transition and important properties of solid state matters in a macroscopic level, due to that fact that it can be controlled conveniently and observed easily and macroscopically in experiments. Lattice waves in the dusty plasma crystals are typical electrostatic modes. Many key plasma parameters can be obtained in studying on the electrostatic dusty plasma waves. Therefore the electrostatic wave study has become a very important diagnostic method for dusty plasmas.The lattice waves in dusty plasmas have been systematically studied in this thesis.Firstly, we make a summary of dusty plasmas and dusty plasma lattices, including their concepts, existence, study methods and recent study situations.Then, we establish a two-dimensional lattice plane model according to the structures of one-dimensional and multi-dimensional lattice. And we talk about the effects of the wake and the vertical forces to on the lattice waves in this model. We analyze the forces to the dusty particles. We study the movement equation of the particles with the considerations of the sheath electric field, the wake and the dusty gravity. And we educe more general dispersion relations.And then, we convert the dispersion relations to exactly forms our need by replacing some parameters in order to fit different study situations. We get four kinds of dispersion relations in one and tow dimensional models: 1, considering effects of the wake, electric filed and the gravity;2, ignoring the wake effects;3, ignoring effects of electric filed and the gravity;4, ignoring effects of the wake, electric filed and the gravity. We get the figures by computer simulations, and compare the different situations.At last, a brief summary is given to end the thesis.