Electron pressure gradient-driven short-wavelength drift-wave instability and its nonlinear evolution

Electron Del p-driven short-wavelength drift-wave oscillations in a magnetized plasma are investigated. Using a kinetic model for the ions and the fluid-guiding center model for the electrons, the authors derive a set of nonlinear mode coupling equations. In the linear limit, dispersion relations are derived under the local approximation, as well as the nonlocal approximation for a sheared magnetic field. Dipolar vortex solutions are shown to exist for the set of nonlinear equations. The parameter space for the existence of localized vortices is presented.