Ultrahigh-speed optical communications

Fiber-based ultrahigh-speed optical communications have achieved a remarkab le level of success reaching multiterabit/s error-free transmission over se veral thousand kilometers. In the near future the total capacity is expecte d to approach a petabit/s. In this article critical issues that are involve d behind the success of these achievements are reviewed and the future dire ction of ultrahigh-speed optical communications is discussed. The idea of t he use of optical solitons for an information carrier is discussed comparat ively with alternative approaches. (C) 2001 American Institute of Physics.