Temperature-insensitive arrayed waveguide gratings on InP substrates

The temperature dependence of wavelength in optical devices is a serious issue in building high-density WDM optical networks. The lasing wavelength of semiconductor lasers and the central wavelength in the semiconductor optical filters have a typical temperature dependence of 1 Å/°C or higher. This is too high for these lasers to be used without temperature control units in WDM systems, which typically have a few hundreds of GHz spacing and temperature variation up to a few tens of degrees centigrade. Recently, we fabricated temperature-insensitive optical filters (TIOF) with the InGaAsP/InP material system. Although the operation principle of the TIOF was clearly verified in that work, the filtering characteristics of the device were relatively unsuitable for multiplexing or demultiplexing devices. In this presentation, by extending the principle of the TIOF to arrayed waveguide grating, we propose a novel temperature-insensitive arrayed waveguide grating and show its highly feasible filtering characteristics for practical applications