Electron-exchange and viscosity effects on propagation of surface plasmons in semi-bounded quantum plasmas

Surface plasmons are collective excitations of electrons at the interface of a metal or plasma with a dielectric or vacuum. Due to their unique properties, this field has found numerous applications in nano-scale electronic devices, biomedical sensors, and electronic signal transmission. Thus, in this paper, we theoretically investigate the propagation of surface plasmon waves on the interface between a vacuum and a quantum plasma by deriving the dispersion relation using the quantum hydrodynamic model and applying boundary conditions. The main focus of the present study is to examine the effect of Fermi electron pressure, quantum Bohm potential, electron-exchange potential, and viscosity on the propagation and decay of surface plasmon waves in semi-bounded collisional quantum plasmas. In the electrostatic limit, the results show that the quantum effects, including Bohm potential and electron-exchange potential, facilitate the propagation of the surface plasmon waves. Also, the collision and viscosity effects have a significant role in the decay of these waves. (author)