New longitudinal waves in electron-positron-ion quantum plasmas
Department of Plasma Physics, E.Andronikashvili Institute of
2 Salam Chair in Physics, GC University, Lahore - 54000, Pakistan
a e-mail: email@example.com
Received in final form: 18 August 2011
Published online: 11 October 2011
A general quantum dispersion equation for electron-positron(hole)-ion quantum plasmas is derived and studied for some interesting cases. In an electron-positron-ion degenerate Fermi gas, with or without the Madelung term, a new type of zero sound waves are found. Whereas in an electron-hole-ion plasmas a new longitudinal quantum waves are revealed, which have no analogies in quantum electron-ion plasmas. The excitation of these quantum waves by a low-density monoenergetic straight electron beam is examined. Furthermore, the Korteweg-de Vries (KdV) equation for novel quantum waves is derived and the contribution of the Madelung term in the formation of the KdV solitons is discussed.
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2011