Joint Center for Advanced High Performance Computing

Applications	  with	  the	  Oakforest-­‐PACS
SALMON:	  Scalable	  Ab-­‐initio	  Light-­‐Matter	  simulator	  for	  Optics	  and	  Nanoscience

GAMERA/GHYDRA

We are developing a computer code SALMON, Scalable Ab-­‐initio Light-­‐Matter simulator forOptics and Nanoscience (http://salmon-­‐tddft.jp). It is based on first-­‐principles time-­‐dependent density functional theory and describes electron dynamics in molecules,
nanostructures, and solids induced by optical electric fields by solving the time-­‐dependent
Kohn-­‐Sham equation in real time and real space. Recently, we have successfully achievedlarge-­‐scale simulations for nano-­‐optics phenomena solving a coupled equation of 3D
Maxwell for light electromagnetic fields and 3D time-­‐dependent Kohn-­‐Sham for light-­‐
induced electron dynamics. It provides an accurate and precise platform of numericalexperiments that will be indispensable in forefront optical sciences.
(a)Enhancement of earthquake simulation for disaster reduction requires fast analysis ofvery large scale low-­‐order finite-­‐element analyses. Group led by Earthquake ResearchInstitute, the University of Tokyo has been developing high-­‐performance low-­‐orderfinite-­‐element solvers by designing algorithms suitable for current computerarchitecture. The developed code was named GAMERA (multi-­‐Grid method, Adaptiveconjugate gradient method, Multi-­‐precision arithmetic, Element-­‐by-­‐element method,pRedictor with Adams-­‐bashworth method). Achievements by GAMERA on the K
computer have been recognized as SC14/SC15 Gordon Bell Prize finalist, and SC16 Best
Poster Award.
GAMERA enabled 1.08 trillion degrees-­‐of-­‐freedom analysis using the full system of theK computer, and the solver attained 18.6% of the peak performance (=1.97 PFLOPS)
Research is continued to attain high-­‐performance on Oakforest-­‐PACS by developing
time-­‐parallel algorithms. The new code is called GHYDRA (Great-­‐HYDRA, HYbird
tempo-­‐spatial-­‐arithmetic multi-­‐griD solveR with concentrated computAtion).
Developed solvers are planned to be used for three-­‐dimensional ground motion
analysis for earthquake disaster estimation, as well as crust-­‐deformation analysis forestimating earthquake generation cycles.
a)	  Earthquake	  wave	  propagationc)	  Evacuation

Surface	  response	  computed	  with	  56	  billion	  degrees-­‐of-­‐freedom	  &	  18	  billion	  element	  crust	  model	  (min.	  element	  size:	  5m)	  	  T	  =	  15	  s.
0	  km(b)(c)
Macroscopic	  system	  (EM	  field)-­‐7	  km

Microscopic	  system	  (TDDFT)

Ikebukuro|E(r, t)|2laser	  field
I=1010W/cm2
ω=3.38eV

Ueno⇢(r, t)2.0	  million	  agents	  evacuating	  to	  nearest	  safe	  site
Post	  Earthquake
earthquake

Shinjuku
Tokyo	  station
Shinbashi
ShibuyaI	  (W/cm2)

109

1010

1011

1012

(a) Performance	  of	  SALMON	  using	  full	  nodes	  of	  Oakforest-­‐PACS.
(b) Optical	  near-­‐field	  generated	  in	  metal-­‐organic	  framework,	  IRMOF10.
(c) Intense	  pulsed	  light	  irradiates	  on	  silicon	  nano-­‐sphere	  of	  250nm	  radius	  by	  coupled	  Maxwell-­‐TDDFT	  calculation.

b)	  Soil	  amplification	  &	  seismic	  structural	  response[Ichimura,	  Fujita et	  al.	  SC15]

Maximum	  response	  of	  328,056	  buildings	  computed	  with	  nonlinear	  frame	  models

Maximum	  surface	  response	  computed	  with	  133,609,306,335	  degrees-­‐of-­‐freedom	  &	  33,212,898,352	  element	  soil	  model	  (min.	  element	  size:	  1m)

Joint	  Center	  for	  Advanced	  HPC	  |	  http://jcahpc.jp/