Ionization Potential Depression Model for Warm/Hot and Dense Plasmas

Abstract For warm/hot and dense plasmas (WDPs), ionization potential depression (IPD) plays a crucial role in determining its ionization balance and understanding the resultant microscopic plasma properties. A sophisticated and unified IPD model is necessary to resolve those existing discrepancies between theoretical and experimental results. However, the applicability of those widely used IPD models nowadays is limited, especially for the nonlocal thermodynamic equilibrium (non-LTE) dense plasma produced by short-pulse laser. In this work, we propose an IPD model that considers inelastic atomic processes, in which three-body recombination and collision ionization processes are found to play a crucial role in determining the electron distribution and IPD for a WDP. This IPD model is validated by reproducing latest experimental results of Al plasmas with a wide-range condition of 70 eV–700 eV temperature and 0.2–3 times solid density, as well as a typical non-LTE system of hollow Al ions. It is demonstrated that the present IPD model has a significant temperature dependence due to the consideration of the inelastic collision processes. With a lower computational cost and wider application range of plasma conditions, the proposed model is expected to provide a promising tool to study the ionization balance and the atomic processes, as well as the related radiation and particle transports properties of the WDP.