The Propagation Characteristic Of Electromagnetic Waves And Surface Waves In Quantum Plasmas

In plasma physics, when the de Broglie wavelength of the charged carriers become comparable to the dimensions of the system (such as inter-particle distances), quantum effects start playing a role. This is so-called quantum plasma. In the quantum plasmas regime, the plasma obeys certain conditions. To the best of our knowledge, there are three well-known models to describe quantum plasma systems, the Wigner-Poisson (WP) model (in the presence of magnetic fields, the so-called Wigner-Maxwell model), Schrodinger-Poisson model and quantum hydrodynamic (QHD) model(in the presence of magnetic fields, the so-called QMHD model). As a fluid model, the QHD (or QMHD) model has its advantage of mathematical efficiency, so it has been extensively used in the study of quantum plasmas transport, waves and instabilities. In our following work, we mainly use the quantum hydrodynamic (QHD) model in the presence of magnetic fields.In quantum plasma physics, the quantum effects stem mainly from three aspects, which is quantum Bohm potential effect, quantum Fermi statistical pressure effect as well as electron spin-1/2effect.Based on the QMHD model, we investigated the quantum effects on the propagation of elliptically polarized extraordinary electromagnetic waves (X waves), and derived a new dispersion relation. Meanwhile, we got the expressions of its group velocity. We found that the group velocity of the extraordinary wave is modified due to the quantum forces and magnetization effects within a certain range of wave numbers. It thus indicated that the quantum spin-1/2effects can reduce the transport of energy in such quantum plasma systems. Our work should be of relevance for the dense astrophysical environments and the condensed matter physics.Furthermore, based on the single-fluid plasma model, a theoretical investigation of surface electromagnetic waves in warm quantum magnetized inhomogeneous plasma is presented. The surface electromagnetic waves are assumed to propagate on the plane between a vacuum and warm quantum magnetized plasma and decay away form the interface. The quantum magnetohydrodynamic (QMHD) model includes quantum diffraction effect (Bohm potential) and quantum statistical pressure is used to derive the new dispersion relation of surface electromagnetic waves. And the general dispersion relation is analyzed in some special cases of interest. It is shown that surface plasma oscillations can be propagated due to quantum effects and the propagation velocity is enhanced. Furthermore, the external magnetic field has a significant effect on surface wave’s dispersion equation. Our work should be of a useful tool for investigating the physical characteristic of surface waves and physical properties of the bounded quantum plasmas.