Compact Low-Loss Optical 72 degrees Hybrid Based on Nonoverlapping-Image Multimode Interference Coupler in Silicon-on-Insulator
Author(s): Li, ZZ (Li, Zezheng); Kuang, YX (Kuang, Yingxin); Guan, H (Guan, Huan); Liu, Y (Liu, Yang); Zhang, XQ (Zhang, Xinqun); Han, WH (Han, Weihua); Li, ZY (Li, Zhiyong)
Source: IEEE PHOTONICS JOURNAL Volume: 11 Issue: 6 Article Number: 7907309 DOI: 10.1109/JPHOT.2019.2956260 Published: DEC 2019
Abstract: A universal principle to achieve different optical hybrids is summarized based on general nonoverlapping-image MMI couplers. An optical 72 degrees hybrid is proposed and demonstrated which is achieved by a 2 x 5 multimode interference (MMI) coupler with length of 89.5 mu m and width of 8.0 mu m. The device is fabricated in silicon-on-insulator (SOI) with 220 nm thick top silicon layer and the buried oxide layer is 3 mu m thick. The proposed device exhibits an extinction ratio larger than 20 dB from 1470.8 nm to 1581.2 nm. The excess loss of optical hybrid is about 1.4 dB and a phase deviation less than +/- 6.0 degrees is obtained with the bandwidth of 51.5 nm.
Accession Number: WOS:000575108400001