Affiliation:
1. Nanjing University of Aeronautics and Astronautics
2. Littin Tech Co., Ltd.
3. University of Cambridge
4. University of California at San Diego
Abstract
The demand for ultra-long waveguides with tunable refractive index keeps growing in various applications, such as tunable delay line, Fourier transform spectrometers, microwave filters, signal processors, programmable photonics circuits, Lidar etc. Thermal tuning using integrated heaters is so far the most popular option to modulate the waveguide index due to simplicity of fabrication, high tuning efficiency, wide tuning range as well as absence of spurious amplitude modulation. But for ultra-long waveguide, the heater design needs to take the in-plane geometry into consideration in order to optimize particular performance metrics. Therefore, in this manuscript we report both theoretical modelling and experimental characterization of integrated heaters for ultra-long waveguides that pays special attention to the impacts of heater geometry.
Funder
National Key Research and Development Program of China
Fast Support Program
Natural Science Foundation of Jiangsu Province
National Natural Science Foundation of China
Fundamental Research Funds for the Central Universities