The Effect Of Charge Gradient On Dust Lattice Wave And Dust Lattice Solitary Wave

Although plasma is the fourth state of matter,it covers almost all the cosmogonic material,and its rich physical phenomena have been widely concerned by scholars.Dusty plasma is an important branch of plasma physics,which has developed rapidly in the last two decades.Because the dust particles in dusty plasma are charged,the collective behavior of dusty plasma is quite different from that of electron-ion plasma.When the electrostatic energy between dust particles exceeds their kinetic energy,dust particles will spontaneously form a dust lattice.Dust lattice belongs to a strong coupling system,and its interaction is more intense and complex,so there will be many instability.Previous studies on the dust lattice wave have always assumed that the charges of dust particles are the same and the interparticle distance between particles is uniform,but in fact,the charge carried by dust particles is affected by the surrounding plasma parameters and the external environment,and thus may have a rather nonuniform distribution inside the experimental chamber.Suppose that the charge carried by the adjacent particles has a certain relationship,called charge gradient.In this paper,the charge gradient effect on the transverse dust lattice wave and dust lattice solitary wave is studied by considering a one-dimensional dust lattice chain model.In Chapter 2,based on the one-dimensional dust lattice chain model,the dispersion relation of transverse dust lattice wave in one-dimensional dust chain with charge gradient effect is derived by adopting the method of classical solid state physics.The results show that the charge gradient plays the role as an external constraint potential,which would make the transverse DLWs be excited without external constraint potential.And the larger the charge gradient effect is,the greater the frequency of the transverse dust lattice wave is.In Chapter 3,starting from the motion equation of dust particles,the Kd V equation of dust lattice solitary waves with charge gradient effect is derived by adopting the reduced perturbation method and the continuous limit method,and its solitary wavesolution is obtained.The numerical results show that the charge gradient effect can affect the propagation of dust lattice solitary waves and sharpen its structure.Finally,the main contents of this paper are summarized and the future work is prospected.