Switching characteristics in variable index arrayed waveguide wavelength selective switch

Abstract

Four wavelength switching was successfully demonstrated in the wavelength selective switch using GaInAs/InP MQW variable index arrayed waveguide by thermo-optic (TO) effect. Four wavelength lights were switched and demultiplexed between the four output ports. IntroductionIn WDM networks, key components are the wavelength multi-/demultiplexers, which combine/separate wavelength channels. Various kind of demultiplexing principles have been proposed and already commercially available, such as arrayed-waveguide gratings (AWG). In the latest paper, a novel wavelength demultiplexer using a GaInAs/InP multiple quantum well (MQW) arrayed waveguide has been proposed in which refractive index varies linearly across the array [1,2]. The conventional AWGs are designed so that phase differences between adjacent waveguides are obtained by gradually varying waveguide length. In the proposed design, however, phase differences between adjacent waveguides are achieved by varying the waveguide thickness which is the refractive indices of the waveguides. Therefore, it is possible to be realized a straight waveguide type wavelength demultiplexer [2]. Furthermore, the device could be applied to wavelength selective switch since the refractive indices of the waveguides in the array can be controlled dynamically by TO effect or QCSE [3,4]. In this report, we show the successful wavelength switching in the wavelength selective switch with linearly varying refractive index arrayed waveguide by controlling the refractive index using TO effect.