Key Laboratory of Opto-electronic Information Technical Science of Ministry of Education, Key Laboratory of Integrated Opto-electronic Technologies and Devices in Tianjin, School of Precision Instruments and Opto-electronics Engineering, Tianjin University, Tianjin, China
Key Laboratory of Opto-electronic Information Technical Science of Ministry of Education, Key Laboratory of Integrated Opto-electronic Technologies and Devices in Tianjin, School of Precision Instruments and Opto-electronics Engineering, Tianjin University, Tianjin, China
Key Laboratory of Opto-electronic Information Technical Science of Ministry of Education, Key Laboratory of Integrated Opto-electronic Technologies and Devices in Tianjin, School of Precision Instruments and Opto-electronics Engineering, Tianjin University, Tianjin, China
Zhaohong Han
Department of Materials Science and Engineering, Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA, USA
Henan Liu
Key Laboratory of Opto-electronic Information Technical Science of Ministry of Education, Key Laboratory of Integrated Opto-electronic Technologies and Devices in Tianjin, School of Precision Instruments and Opto-electronics Engineering, Tianjin University, Tianjin, China
Jurgen Michel
Department of Materials Science and Engineering, Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA, USA
Lionel C. Kimerling
Department of Materials Science and Engineering, Microphotonics Center, Massachusetts Institute of Technology, Cambridge, MA, USA
Key Laboratory of Opto-electronic Information Technical Science of Ministry of Education, Key Laboratory of Integrated Opto-electronic Technologies and Devices in Tianjin, School of Precision Instruments and Opto-electronics Engineering, Tianjin University, Tianjin, China
To mitigate the temperature sensitivity of photonic devices, materials with a negative thermo-optical coefficient (TOC) are integrated to optical waveguides. However, previously reported waveguides are made athermal at only one wavelength. In this paper, we theoretically propose a new broadband athermal waveguide, which consists of TiO2 with a negative TOC and SiC with a positive TOC in its core. This composite core shows a near-zero broadband effective TOC, i.e., ±1x10-6/K over a 780-nm bandwidth from 1280 to 2060 nm. Furthermore, it also has low anomalous dispersion, from 66 to 329 ps/nm/km in the same wavelength range. This new athermal waveguide, when used to form microresonators, enables us to achieve broadband nonlinear applications with negligible intra-cavity thermal dynamics on a chip. We also show that the proposed waveguide can be tightly bent without suffering from a large bending loss/substrate leakage, which is suitable for dense integration.
