Surface photoeffect and optical absorption: Maxwell equations in tensor and nonlocal isotropic approximation

Abstract

The surface photoeffect is studied for a þ polarized continuous laser with an angular frequency ω in the long wave length (LWL) domain, i.e. λ≥ 100Å. In this LWL domain the laser fields are usually taken to be constant in space, an approximation called LWL approximation. However, perpendicular to a gas-solid interface, the potential, the electron density and the laser fields vary on a sub-nanometric scale. Here, these varying laser fields are solutions of the combined Ampère-Maxwell and material equations. The material functions are taken to be either scalar or tensor. They are a function of the unperturbed electron density of the material system calculated from the Schr\"odinger equation. For a planar structureless gas-solid interface and a þ polarized laser, the Ampère-Maxwell equation in real space reduces to a set of coupled first and second order ordinary differential equations in one dimension. For an Al(001) surface calculation using model jellium and DFT/LDA potentials, the total absorbed power density of the laser and the number of electrons escaping from the surface, display monopole and multipole surface plasmon resonances and a minimum near the bulk plasmon resonance found by other calculations and in experiments. [DOI: 10.1380/ejssnt.2009.249]