Electrostatic Nonlinear Structures in Dissipative Electron--Positron--Ion Quantum Plasmas

Low frequency (in comparison to ion plasma frequency) ion-acoustic shocks and solitons in superdense electron--positron--ion quantum plasmas are studied. The quantum hydrodynamic model is used incorporating quantum Bohm forces and Fermi--Dirac statistical corrections to derive the deformed Korteweg de Vries--Burgers (dKdVB) equation in weakly nonlinear limit. The travelling wave solution of dKdVB equation is presented and results are discussed in different limits. It is found that shock height increases with increase of quantum pressure, positron concentration and dissipation. Further, it is seen that the width of soliton decreases with increase of quantum pressure.