Abstract

We consider the feasibility of performing logic with optical fibers at low powers. A Mach-Zehnder interferometer consists of two optical fibers. We consider the circular interference fringes between the outputs of the two fibers. A laser beam with a different wavelength is coupled into one of the two fibers to provide an increased intensity in that fiber. This effect will cause the index of refraction to change in that fiber because of nonlinearity. Since the interference fringes are very sensitive, a small change due to phase modulation will cause the pattern to move. Therefore, we do not need high power. The different combinations of the input presence and absence for the two laser beams will give different interference patterns at the output. Logical operations are obtained if a detector is placed at a particular position in the output.

© 1992 Optical Society of America