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arXiv · 1210.1531

Ten-million-atom electronic structure calculations on the K computer with a massively parallel order-N theory

Takeo Hoshi·Yohei Akiyama·Tatsunori Tanaka·Takahisa Ohno
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Abstract

A massively parallel order-N electronic structure theory was constructed by an interdisciplinary research between physics, applied mathematics and computer science. (1) A high parallel efficiency with ten-million-atom nanomaterials was realized on the K computer with upto 98,304 processor cores. The mathematical foundation is a novel linear algebraic algorithm for the generalized shifted linear equation. The calculation was carried out by our code ' ELSES ' (www.elses.jp) with modelled (tight-binding-form) systems based on ab initio calculations. (2) A post-calculation analysis method, called pi-orbital crystalline orbital Hamiltonian population (pi-COHP) method, is presented, since the method is ideal for huge electronic structure data distributed among massive nodes. The analysis method is demonstrated in an sp2-sp3 nano-composite carbon solid, with an original visualization software 'VisBAR'. The present research indicates general aspects of computational physics with current or next-generation supercomputers.

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Takeo Hoshi, Yohei Akiyama, Tatsunori Tanaka, Takahisa Ohno. 2012-12-04. Ten-million-atom electronic structure calculations on the K computer with a massively parallel order-N theory. https://doi.org/10.7566/jpsj.82.023710

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