In this paper, we demonstrate a novel all-fiber wavelength-tunable acoustooptic switch utilizing intermodal coupling in a two-mode fiber (TMF). Its all-fiber configuration consisting of a fiber acoustooptic tunable filter and a mode-selective coupler results in the low loss (< 2~dB) operation. The operating bandwidth >50~nm, the switching time of 40 µ sec, and the crosstalk of 20 dB were achieved. By controlling the design parameters of the two-mode fiber, the 3-dB bandwidth of the switched signal was varied from 2.5 nm to >35~nm. A novel all-fiber dynamic optical add-drop multiplexer is also demonstrated using two acoustooptic switches in series.
Hee Su Park, Kwang Yong Song, Seok Hyun Yun, and Byoung Yoon Kim, "All-Fiber Wavelength-Tunable Acoustooptic Switches Based on Intermodal Coupling in Fibers," J. Lightwave Technol. 20, 1864- (2002)