Nonlinear lower-hybrid drift soliton in multi-component plasmas

We investigate the nonlinear structure of the lower-hybrid drift wave in multi-component plasmas. The Korteweg-de Vries (KdV) equation is derived and a localized soliton is found. Depending on the plasma parameters, the amplitude of the soliton can vary monotonically or nonmonotonically with the impurity ion content. Interestingly, the amplitude can even become negative and accordingly the soliton collapses from original humps to a cavity. We show the conditions that determine the monotonicity of the amplitude with the impurity ion content and the collapse of the soliton. In addition, we show that the monotonicity of the width of the soliton with respect to the impurity ion content is determined solely by the difference in the electron temperature gradient and electron density gradient. Our results highlight the effect of the impurity of ions on the structure of the lower-hybrid drift soliton.