Photoionization cross-section of isotropic defects or impurity centers in isolators

作者:Lima H*; Batista J V; Couto dos Santos M A
来源:EPL, 2016, 115(3): 33002.
DOI:10.1209/0295-5075/115/33002

摘要

An analytical expression to calculate the photoionization cross-section of isotropic defects or impurity centers is being proposed by using the time-dependent perturbation theory. The ground-state wave function of the electron captured in the impurity state is described by a three-dimensional isotropic harmonic oscillator and the electron excited state in the continuum conduction band is described by a plane wave. The expression has been obtained considering all multipoles terms in the Hamiltonian, and that the radiation field which interacts with electrons is semi-classical and linearly polarized. This approximation is assumed because the effects of the linear contribution are dominant. The available data of the Al2O3:C and Lu2SiO5:Ce systems are in good agreement with our predictions. Such satisfactory comparison is a strong indication that the present model can be used to provide good predictions of the photoionization cross-section in several areas.

  • 出版日期2016-8