Temporal responses of a symmetric self-electro-optic effect device based on Wannier–Stark localization

Abstract

We have experimentally and theoretically investigated responses to optical pulse excitation of a symmetric self-electro-optic effect device (S-SEED) consisting of two GaAs/AlAs superlattice diodes. Transient optical responses exhibit pronounced oscillations due to successive Stark-ladder resonances induced by temporal variations of the applied voltage to each diode. In addition, it is found that steady state optical responses strongly depend on the pulse width and/or height of the optical excitation pulses. These results have shown that the switching mechanism of the S-SEED is governed by the voltage balance between the diodes induced by photogenerated charge transport. We clearly analyze the experimental voltage-switching process based on the potential function theory. By using well-controlled optical pulses, we demonstrate the optical switching between arbitrary stable states predicted by the local minima of the potential function.