Toroidal electron temperature gradient driven drift modes

The electron temperature gradient in tokamak geometry is shown to drive a short wavelength lower hybrid drift wave turbulence resulting from the unfavorable magnetic curvature on the outside of the torus. Ballooning mode theory is used to determine the stability regimes and the complex eigenfrequencies. At wavelengths of the order of the electron gyroradius, the polarization is electrostatic and the growth rate is greater than the electron transit time around the torus. At longer wavelengths of the order of the collisionless skin depth, the polarization is electromagnetic with electromagnetic vortices producing the dominant transport. The small scale electrostatic component of the turbulence produces a small, of order (me/mi)1/2, drift wave anomalous transport of both the trapped and passing electrons while the c/ωpe scale turbulence produces a neo-Alcator [Nucl. Fusion 25, 1127 (1985)] type transport from the stochastic diffusion of the trapped electrons.