A general solution to the Schrodinger-Poisson equation for a charged hard wall: Application to potential profile of an AlN/GaN barrier structure

作者：Berland Kristian^*

来源：Superlattices and Microstructures, 2011, 50(4): 411-418.

DOI：10.1016/j.spmi.2011.08.003

• Schrodinger-Poisson equation
• Two-dimensional electron gas
• Interfaces
• Surface states
• AlN/GaN heterostructures
• Band bending

A general, system-independent, formulation of the parabolic Schrodinger-Poisson equation is presented for a charged hard wall in the limit of complete screening by the ground state. It is solved numerically using iteration and asymptotic boundary conditions. The solution gives a simple relation between the band bending and sheet charge density at an interface. Approximative analytical expressions for the potential profile and wave function are developed based on properties of the exact solution. Specific tests of the validity of the assumptions leading to the general solution are made. The assumption of complete screening by the ground state is found be a limitation; however, the general solution provides a fair approximate account of the potential profile when the bulk is doped. The general solution is further used in a simple model for the potential profile of an AlN/GaN barrier structure. The result compares well with the solution of the full Schrodinger-Poisson equation.

• 出版日期2011-10