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DOE OSTI · 2429767

QRCODE: Massively parallelized real-time time-dependent density functional theory for periodic systems

Choi, Min·Okyay, Mahmut Sait·Dieguez, Adrian Perez·Ben, Mauro Del·Ibrahim, Khaled Z.·Wong, Bryan M.
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Abstract

We present a new software module, QRCODE (Quantum Research for Calculating Optically Driven Excitations), for massively parallelized real-time time-dependent density functional theory (RT-TDDFT) calculations of periodic systems in the open-source Qbox software package. Our approach utilizes a custom implementation of a fast Fourier transformation scheme that significantly reduces inter-node message passing interface (MPI) communication of the major computational kernel and shows impressive scaling up to 16,344 CPU cores. In addition to improving computational performance, QRCODE contains a suite of various time propagators for accurate RT-TDDFT calculations. As benchmark applications of QRCODE, we calculate the current density and optical absorption spectra of hexagonal boron nitride (h-BN) and photo-driven reaction dynamics of the ozone-oxygen reaction. We also calculate the second and higher harmonic generation of monolayer and multi-layer boron nitride structures as examples of large material systems. Our optimized implementation of RT-TDDFT in QRCODE enables large-scale calculations of real-time electron dynamics of chemical and material systems with enhanced computational performance and impressive scaling across several thousand CPU cores.

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97 MATHEMATICS AND COMPUTINGElectron dynamicsHarmonic generationMassive parallelizationPeriodic systemsQuantum dynamicsReal-time time-dependent density functional theory

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Choi, Min, Okyay, Mahmut Sait, Dieguez, Adrian Perez, Ben, Mauro Del, Ibrahim, Khaled Z., Wong, Bryan M.. 2024-08-14. QRCODE: Massively parallelized real-time time-dependent density functional theory for periodic systems. https://doi.org/10.1016/j.cpc.2024.109349

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