Generation of undamped exciton-biexciton beats in InAs quantum dots using six-wave mixing

Spyridon G. Kosionis, Dimitrios P. Alevizos, Emmanuel Paspalakis

Paola Borri, W. Langbein

Hirokazu Tahara, Yoshihiro Ogawa, F. Minami +2 more

We report the generation of undamped exciton-biexciton beats for coherent dynamics of excitons in InAs quantum dots at telecommunication wavelengths. The exciton-biexciton beat is damped rapidly in four-wave mixing measurements, but a six-wave mixing technique with three excitation pulses enables us to regenerate and control the exciton-biexciton beat perfectly. We have demonstrated the complete regeneration of the exciton-biexciton beat by adjusting the delay time between the first and second excitation pulses. This approach is different from conventional coherent control in quantum dots. Furthermore, the initial phase of the exciton-biexciton beat is controlled by using this technique. We show that the generation of undamped beats is a powerful tool for controlling quantum states.

Junko Ishi‐Hayase, Kouichi Akahane, Naokatsu Yamamoto +3 more

We perform a transient four‐wave mixing experiment to investigate the initial dynamics of the time evolution of exciton coherence in highly‐stacked InAs quantum dots. For short time delays, an oscillatory behavior with a period of 31 ps is observed only in the weak excitation regime. The excitation density and polarization dependence of this oscillation cannot be explained by the usual quantum beat phenomena such as biexcitonic and bright excitonic beats.

Hideki Gotoh, Hidehiko Kamada, T. Saitoh +2 more

Aoki, Svirko, Kuwata-Gonokami