Abstract

A narrow-bandwidth, broad-range tunable filter based on InGaAsP/InP is potentially one of the key devices for wavelength and optical switching in future optical fiber communication systems. Using current injection, a filter with wavelength tuning over 80 nm has been demonstrated in a vertically coupled directional coupler.¹ Integrating an optical amplifier with a grating-assisted vertical coupler, a broad tunable (> 57 nm) laser has also been obtained.² With >300-nm-wide low-loss window available in the optical fiber, it is important to explore the physical limitations to the tuning range of the filter.

© 1993 Optical Society of America