Abstract

Quasi-periodic structures, structures which are intermediate between the periodic and disordered systems, have been a subject of considerable theoretical interest in recent years^1–3. It has been shown theoretically that such structures display exotic behavior such as weak localization and scaling. Experimental realization of such structures and identification of these exotic features is needed. One potentially simple experiment towards this end has recently been proposed² where a stack of dielectric layers is constructed using two types of dielectric layers arranged in a Fibonacci sequence. The transmission coefficient, as a function of the wavelength of incident light, was demonstrated to be multifractal and displayed scaling. Our work is concerned with a quasi-periodic optical system consisting of waveguide directional couplers which under certain resonant conditions displays localization and scaling. The energy exchange between the guides is codirectional as opposed to the contradirectional energy exchange of Ref. 2.

© 1989 Optical Society of America