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arXiv · 1311.1355

Imaginary time propagation code for large-scale two-dimensional eigenvalue problems in magnetic fields

P. J. J. Luukko·E. Räsänen
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Abstract

We present a code for solving the single-particle, time-independent Schrödinger equation in two dimensions. Our program utilizes the imaginary time propagation (ITP) algorithm, and it includes the most recent developments in the ITP method: the arbitrary order operator factorization and the exact inclusion of a (possibly very strong) magnetic field. Our program is able to solve thousands of eigenstates of a two-dimensional quantum system in reasonable time with commonly available hardware. The main motivation behind our work is to allow the study of highly excited states and energy spectra of two-dimensional quantum dots and billiard systems with a single versatile code, e.g., in quantum chaos research. In our implementation we emphasize a modern and easily extensible design, simple and user-friendly interfaces, and an open-source development philosophy.

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P. J. J. Luukko, E. Räsänen. 2015-11-20. Imaginary time propagation code for large-scale two-dimensional eigenvalue problems in magnetic fields. https://doi.org/10.1016/j.cpc.2012.09.029

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