93 citations · 133 across the 2 of their papers we have counts for
4 papers
Random phase vector for calculating the trace of a large matrix
Toshiaki Iitaka, Toshikazu Ebisuzaki
We derive an estimate of statistical error in calculating the trace of a large matrix by using random vector, and show that {\em random phase vector} gives the results with the sma…
Methane Hydrate under High Pressure: Searching for Centering of Hydrogen Bonds
Toshiaki Iitaka, Toshikazu Ebisuzaki
The structural, electronic, and spectroscopic properties of a high-pressure phase of methane hydrate (MH-III) are studied by first principles electronic structure calculations. A d…
Non-degenerate Two Photon Absorption Spectra of Si Nanocrystallites
Toshiaki Iitaka, Toshikazu Ebisuzaki
We propose an efficient linear-scaling time-dependent method for calculating nonlinear response function, and study the size effects in non-degenerate two photon absorption spectra…
Computing the real-time Green's Functions of large Hamiltonian matrices
Toshiaki Iitaka
A numerical method is developed for calculating the real time Green's functions of very large sparse Hamiltonian matrices, which exploits the numerical solution of the inhomogeneou…