The forced oscillator method incorporating the fast time-evolution algorithm Original Research Article

The forced oscillator method (FOM) is a powerful algorithm to calculate linear response functions of quantum systems represented by very large Hamiltonian matrices. We demonstrate the efficiency of the FOM by applying for the calculation of the ac conductivity σ(ω) for two-dimensional electron systems with spin-orbit interactions, for which conventional numerical methods are inoperative. It is shown that the efficiency of the FOM is greatly enhanced by combining the fast time-evolution method.