Cubic-scaling iterative solution of the Bethe-Salpeter equation for finite systems
FERRARI, Francesco
Dipartimento di Scienza dei Materiali
Donostia International Physics Center [DIPC]
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Dipartimento di Scienza dei Materiali
Donostia International Physics Center [DIPC]
FERRARI, Francesco
Dipartimento di Scienza dei Materiali
Donostia International Physics Center [DIPC]
Dipartimento di Scienza dei Materiali
Donostia International Physics Center [DIPC]
SANCHEZ-PORTAL, Daniel
Centro de Fisica de Materiales [CFM]
Donostia International Physics Center [DIPC]
< Reduce
Centro de Fisica de Materiales [CFM]
Donostia International Physics Center [DIPC]
Language
en
Article de revue
This item was published in
Physical Review B: Condensed Matter and Materials Physics (1998-2015). 2015-08-17, vol. 92, n° 7, p. 075422 (1-18)
American Physical Society
English Abstract
The Bethe-Salpeter equation (BSE) is currently the state of the art in the description of neutral electron excitations in both solids and large finite systems. It is capable of accurately treating charge-transfer excitations ...Read more >
The Bethe-Salpeter equation (BSE) is currently the state of the art in the description of neutral electron excitations in both solids and large finite systems. It is capable of accurately treating charge-transfer excitations that present difficulties for simpler approaches. We present a local basis set formulation of the BSE for molecules where the optical spectrum is computed with the iterative Haydock recursion scheme, leading to a low computational complexity and memory footprint. Using a variant of the algorithm we can go beyond the Tamm-Dancoff approximation (TDA). We rederive the recursion relations for general matrix elements of a resolvent, show how they translate into continued fractions, and study the convergence of the method with the number of recursion coefficients and the role of different terminators. Due to the locality of the basis functions the computational cost of each iteration scales asymptotically as $O(N^3)$ with the number of atoms, while the number of iterations is typically much lower than the size of the underlying electron-hole basis. In practice we see that , even for systems with thousands of orbitals, the runtime will be dominated by the $O(N^2)$ operation of applying the Coulomb kernel in the atomic orbital representationRead less <
English Keywords
Excited states: methodology
Molecular spectra
Strongly correlated electron systems: generalized tight-binding method
ANR Project
Prédiction par calcul numérique intensif du potentiel à circuit ouvert au sein de cellules photovoltaïques organiques. - ANR-12-MONU-0014
Origin
Hal imported