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Progress in ultrafast optoelectronics

The reason why optoelectronic is one of the most promising technologies for future information society lies in the potential of high density packing of photons in time, frequency or space domains. This feature already is proven by the success of fiber optic telecommunication or by high density optical disc storage. The ultimate performance restricted by the physical principle, however, is yet to come (1)(2). Specifically in time domain, the fruits of scientific researches on femtosecond laser pulses(3) are not yet fully exploited in information technologies. In Japan a considerable amount of efforts have been paid on the basic study of ultrafast optics, such as the university joint research program (4), or government-industrial research consortium entitled "femtosecond technology"(5). The present review emphasizes the hardware aspects of the recent progress in ultrafast optoelectronics and touches also some of the future prospect on application fields.