Abstract

All-optical switching will be a key technology for implementing a high-speed optical signal processing. We reported all-optical bistable¹ and AND-logic operation² in DFB waveguides. In the results reported in,^1,2 the polarization of input light should be strictly controlled, since those devices have polarization dependence. For a practical application, polarization independent switching function is strongly required. Deep-ridge waveguide structure makes it possible to eliminate the structural birefringence by adjusting the waveguide width. Recently, we clarified that the birefringence of DFB waveguide switch has been nearly eliminated by using deep-ridge structure.³ In this paper, the first demonstration of polarization-independent all-optical switching is reported in a nonlinear DFB waveguide with vertically etched grating. Besides, polarization independence of grating coupling coefficient was also accomplished by adjusting grating depth.

© 2002 Optical Society of America