2 research outputs found
AbinitGUI : what's up, doc ?
No full textAbinitGUI is a project designed to give easy, fast and intuitive tools for people dealing with the Abinit software. At every step of the computations, these tools allow to avoid cumbersome and repetitive manual tasks, from connection and submission of jobs on remote machines towards post-processing of the results via the pre-processing of the input file... This presentation mainly consists in an online demonstration of the software where the main features are explained, focusing on the new features that have been developed during the last two years
Efficient Trilinear Interpolation Technique for Bethe-Salpeter Calculations of Optical Spectra
No full textThe inclusion of excitonic effects in semiconductors with the Bethe-Salpeter equation leads to good agreement of the optical spectra with experimental measurements. However, this approach requires in general very fine meshes of wavevectors in the Brillouin Zone in order to obtain well-converged spectra, with very heavy computational load, preventing access to numerous derived quantities, as e.g. Raman intensities [1]. We present a new methodology that allows to decrease the work load to reach a given accuracy. This technique is based on a trilinear interpolation technique within the Brillouin zone, combined with the Lanczos algorithm and double-grid technique, in the spirit of Refs. [2] and [3], to achieve efficient speed-up and memory use. The technique is benchmarked in terms of accuracy on selected test cases. The scaling has also been studied from low to very-high density of points in the Brillouin Zone, showing a much better scaling than a complete Bethe-Salpeter. This approach might be used in the future for more complex calculations of optical properties. References [1] Y. Gillet, M. Giantomassi, and X. Gonze, Phys. Rev. B 88, 094305 (2013). [2] M. Rohlfing and S. G. Louie, Phys. Rev. B 62, 4927 (2000). [3] D. Kammerlander, S. Botti, M. A. L. Marques, A. Marini and C. Attaccalite, Phys. Rev. B 86, 125203 (2012)
