Separate spin evolution of electrostatic energy flow in a degenerate quantum plasma

Abstract

We have discussed energy densities and energy flow speed in a spin polarized plasma when longitudinal waves [Spin electron acoustic wave (SEAW) and Langmuir wave] propagate through the plasma. Employing the separate spin evolution quantum hydrodynamic model, we have derived the expression for energy densities and energy flow speed. It is found that the spin polarization changes the profiles of various energy densities. Specifically, we find that the spin polarization broadens the profile of the electrostatic energy density retaining the same peak value. In the case of kinetic and quantum energy densities, the profiles become narrower with the decrease in the peak value for the former case and increase for the latter. On the other hand, in the case of Langmuir waves, the spin polarization effect is similar for electrostatic energy density but opposite to the peak values of kinetic and quantum energy densities. The corresponding profiles become narrower as in the case of SEAW. Furthermore, energy flow speed associated with the SEAW and Langmuir wave is reduced for higher values of spin polarization. It is also noted that the contribution of Bohm potential in the dispersion compensates the reduction of energy flow due to spin polarization. The results are graphically analyzed for the choice of solid state plasma parameters.