4月26日(木)  15:00 -- 16:00  大谷 佳広 (京都大学情報学研究科)
            ``周期境界値問題における高速多重極法''

＜研究発表要旨＞
We have developed an FMM (Fast Multipole Method) for wave problems with 
periodic conditions. The periodic Green function is an important ingredient 
in our formulation, which is computed efficiently with the help of the 
Fourier analysis. We then apply the proposed method to the analysis in 
Helmholtz' equation and Maxwell's equations. In the case of Helmholtz' 
equation, we deal with scattering problems with periodic array of cracks 
and plot the energy transmittances versus wave numbers. The stopband and 
related phenomena are observed clearly. Typical advanced applications of 
such problems are photonic crystals and  meta materials, which get 
increased attention these days.