Power-efficient silicon nitride thermo-optic phase shifters for visible light
Zheng Yong, Hong Chen, Xianshu Luo, Alperen Gövdeli, Hongyao Chua, Saeed Sharif Azadeh, Andrei Stalmashonak, Guo‐Qiang Lo, Joyce K. S. Poon, Wesley D. Sacher
Abstract
We demonstrate power-efficient, thermo-optic, silicon nitride waveguide phase shifters for blue, green, and yellow wavelengths. The phase shifters operated with low power consumption due to a suspended structure and multi-pass waveguide design. The devices were fabricated on 200-mm silicon wafers using deep ultraviolet lithography as part of an active visible-light integrated photonics platform. The measured power consumption to achieve a π phase shift (averaged over multiple devices) was 0.78, 0.93, 1.09, and 1.20 mW at wavelengths of 445, 488, 532, and 561 nm, respectively. The phase shifters were integrated into Mach-Zehnder interferometer switches, and 10 - 90% rise(fall) times of about 570(590) μs were measured.