Modified relation for laser-plasma electron density measurement using x-ray interferometry

摘要

In this paper, the linear propagation of x rays in laser produced plasma is studied theoretically, with a quantum mechanical technique and the so-called V representation, where the representation transformation is made by using the potential Hamiltonian V. A modified expression relating the phase difference between the probe and the reference x ray light to the plasma electron density is derived, in which the electron density gradient and its higher-order effects are taken into account. The coupling relation between phase and amplitude of x-ray is derived, and the solutions with higher-order corrections are given. An important parameter is given, which is related to the errors of the electron density measurement using x-ray interferometry. It is depicted that providing the parameter is less then one, the x-ray interferometry can be used for the measurement of the electron density, while, the greater value of the parameter, the higher order modifications need to make.