Development of Low Loss Ultra-High Δ ZrO₂-SiO₂ PLC for Next Generation Compact and High-Density Integrated Devices

Abstract

For next generation planar lightwave circuit (PLC) devices, high function and high-density integration are required as well as downsizing and cost reduction. To realize these needs, high refractive index difference between a core and a clad (Δ) is required. To use PLC for practical applications, silica-based PLC is one of the most attractive candidate. However, degradation of the optical properties and productivity occur when Δ of the core becomes high. Thus, Δ of most of the conventional PLC with GeO₂-SiO₂ core is designed less than 2.5%. In this paper, we report a silica-based ultra-high Δ PLC with ZrO₂-SiO₂ core. 5.5%-Δ ZrO₂-SiO₂ PLC has been realized with low propagation loss and basic characteristics has been confirmed. Potential of chip size reduction of the ZrO₂-SiO₂ PLC is shown.