The Multi-component Particle Effect And Spin Effect In Quantum Plasmas

In the recent decades, quantum effects in plasmas has drawn considerableattention of researchers. Quantum plasmas has a wide range of applications indifferent environments. Quantum effects in dusty plasmas has also been proverbiallyconcerned, while most of the researches are focused on mono-sized quantum dustyplasma. In fact, a dusty plasma consists of many different dust grains with differentsize. In this paper, we considered the effect of dust size distribution on the quantumdusty plasmas. Besides, spin characteristics can cause many interesting effects inthe quantum plasmas. The dissertation mainly discusses the following contents:1. By employing the quantum hydrodynamic model for electron-ion-dustplasma, we derive a dispersion relation of he quantum dusty plasma. The effects of thedust size distribution on the dispersion relation in a cold quantum dusty plasma arestudied. Both analytical and numerical results are given to compare the differencesbetween the dusty plasma with considering the dust size distribution and themono-sized dusty plasma. It is shown that many system parameters can significantlyinfluence the dispersion relation of the quantum dusty plasma.2. Starting from the governing equations for a quantum magnetoplasma includingthe electron spin12effect and quantum Bohm potential, we deriveKorteweg-deVries (KdV) equation of the system of quantum magneto-hydrodynamics(QMHD). The amplitude and width of magnetosonic soliton with different parametersin the system are studied. It is found that the normalized Zeeman energy E plays acrucial role, for E≥1the amplitude and the width of solitary wave all decrease as Eincreases. That is, the introduction of spin quantum force modifies the shape ofsolitary magnetosonic waves and makes them more narrower and shallower.