First-principle real-time calculation for the dynamical Franz-Keldysh effect

Otobe, Tomohito; Shinohara, Yasushi*; Sato, Shunsuke*; Yabana, Kazuhiro*

We present the first-principle real-time simulation for the modulation of the dielectric functionunder an intense mid-infrared coherent light, dynamical Franz-Keldysh effect (DFKE), of the diamond. Our result shows that the change of the dielectric function is large at the minimum of the pump light field at low intensity region, and the phase shift of the DFKE signals occurs as the pump light field increases. We ascribe this phase shift to the competitive effect of multiphoton processes.