The programm package KSAP, "Kieler Software for Angular Resolved
Photoemission", has been successively developed by Juergen Henk,
Claus-Henning Solterbeck, Anke Boedicker, Thomas Strasser in the group of
Wolfgang Schattke at the Institut fuer Theoretische Physik und Astrophysik
of CAU Kiel.
KSAP calculates the photocurrent from solid surfaces of semiconductor
materials. The photocurrent is obtained within the one-step model based
on the "golden rule" formulation of the photoemission process. The
electronic structure of the initial states is determined by the calculation
of the half-space Green's matrix, taking into account relaxation and
reconstruction of the surface. The Green's matrix is given in a layer
resolved linear combination of atomic orbitals.
The final state of photoemission is obtained as a scattering state with
asymptotic boundary conditions. The wave function of the final state is
determined by matching the solution of the complex band structure to the
vacuum solution, representing the surface by a step potential. The solution
within the bulk is calculated by the empirical pseudopotential method.
The transition matrix elements between the final state and the layer Bloch
sums of the initial state are calculated in real space, using good lattice points.
The program has been applied to photoemission from Si, GaAs, GaN, InP,
CdTe and AlAs surfaces, taking into acount relaxation and reconstruction at
(001) as well as at (110) surfaces.
The program is written in Fortran and uses the NAG library for a few specific
algorithms. It was tested on various UNIX platforms.
Further information about the KSAP package is available in the documentation
section, in german language, however. Some background ist given in the references.