A Polarization Multiplexing Optical Circuit for Efficient Phase Tuning

• Published in: IEEE photonics technology letters Vol. 31; no. 19; pp. 1549 - 1552
• Main Authors: Shu, Haowen, Deng, Qingzhong, Wang, Xingjun, Jin, Ming, Tao, Yuansheng, Zhou, Zhiping
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.10.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Circuits; Energy conservation; Multiplexing; Optical device fabrication; Optical imaging; Optical polarization; Optical waveguides; Phase shift; Phase shifters; Polarization; Silicon; silicon on insulator technology; Tuning
• ISSN: 1041-1135; 1941-0174
• DOI: 10.1109/LPT.2019.2937913

The high efficiency on-chip optical phase shifters are required in almost every photo-electronic integration systems. In this work, we present a novel silicon optical circuit for the efficient phase shifiting. A polarization multiplexing scheme is proposed to improve the effective phase tuning length. The circuit is fabricated and in depth analyzed, exhibiting a 3.57 times effective group optical length enhancement compared with the traditional design. Moreover, A thermal-tuning phase shift based on such polarization multiplexing structure was experimentally demonstrated. Within the size of <inline-formula> <tex-math notation="LaTeX">75 \times 320~\mu \text{m}^{2} </tex-math></inline-formula>, a 63.8% power saving for thermal phase shift was measured in the proposed circuit. With considerable efficiency, such circuit is expected to serve as a general underlying structure for the silicon based integrated phase tuning.