Effect of electron temperature gradient on the modulational instability of drift waves and anomalous transport due to drift-wave turbulence

A nonlinear drift-mode equation including the effect of an electron-temperature gradient has been derived. To discuss modulational instability, we have obtained a nonlinear evolution equation for the drift mode from a third-order secularity-elimination condition using a multiple time- and space-scales technique. The effect of localized structure on the transport process has been investigated.