Effect of electron-density gradient on the propagation of beam in an inhomogeneous plasma

In the study of the propagation of light in an inhomogeneous isotropic medium such as the plasma, the customary approximation of neglecting the effect of electron-density gradient is not accurate. In this paper, we are concerned with continuous variable linear index of effective plasma refraction and the effect of plasma electron-density gradient on the beam parameters. To understand the effect of the electron-density gradient more clearly, the numerical simulation will be made. We find that the larger the propagation distance and the higher the distribution of the plasma electron density is, the greater the effective becomes.