Takahashi Hiroshi

The fabrication of a UV written grating in silica-based waveguide and an integrated external cavity laser composed of the grating and a spot-size converter integrated LD on planar lightwave circuit platform is described. The proposed structure provides a low loss laser cavity, which enables a stable single mode oscillation with threshold current of 12mA. The side mode suppression ratio is 37 dB and the average thermal coefficient is as low as-1.7 GHz/degree. Multiwavelength light source composed of the external cavity lasers with 2 nm spaced four wavelength are also realized with the same technique. It is shown that the proposed laser has a potential to be used in practical WDM systems.

The silica-based Planar Lightwave Circuits (PLCs) offers versatile optical signal processing functions such as wavelength division multiplexing (WDM). Therefore, the hybrid integration of the PLCs and the semiconductor opto-electronic devices is promising technology to realize advanced optical communication systems such as an optical access networks and a WDM optical networks. In order to realize the hybrid integration, we developed a PLC platform which consists of the device assembly region and the electrical wire region together with a PLC region. This paper describes the recent progress of our hybrid integration technology.