Publication: IEICE TRANSACTIONS on Electronics Publication Date: 2002/01/01 Vol. E85-CNo. 1pp. 167-173 Type of Manuscript: INVITED PAPER (Special Issue on Ultrafast Optical Signal Processing and Its Application) Category: Ultrafast All-Optical Switching, Optical Delay and Waveform Control Keyword: squarylium, J aggregates, optical switch, Tbps, femtosecond,