Program title: trap.x
Catalogue identifier: AEBB_v1_0
Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEBB_v1_0.html
Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland
Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html
No. of lines in distributed program, including test data, etc.: 17 750
No. of bytes in distributed program, including test data, etc.: 205 138
Distribution format: tar.gz
Programming language: mostly Fortran 90
Computer: PCs—SUN, HP Alpha, IBM
Operating system: Linux, Solaris, Tru64, AIX
Classification: 7.7
Nature of problem: The simplest description of a spin ; trapped system at the mean field level is given by the Hartree–Fock method. This program presents an efficient approach to solving these equations. Additionally, this program can solve for time-independent Gross–Pitaevskii and Hartree–Fock equations for bosonic atoms confined in a harmonic trap. Thus the combined program can handle mean-field equations for both the Fermi and the Bose particles.
Solution method: The solutions of the Hartree–Fock equation corresponding to the Fermi systems in atomic traps are expanded as linear combinations of simple-harmonic oscillator eigenfunctions. Thus, the Hartree–Fock equations which comprise a set of nonlinear integro-differential equations, are transformed into a matrix eigenvalue problem. Thereby, solutions are obtained in a self-consistent manner, using methods of computational linear algebra.
Running time: The run times of example jobs are from a few seconds to a few minutes. For jobs involving very large basis sets, the run time can extend into hours.