Title :
CMOS-Compatible Vertical Grating Coupler With Quasi Mach–Zehnder Characteristics
Author :
Zanyun Zhang ; Zan Zhang ; Beiju Huang ; Chuantong Cheng ; Hongda Chen
Author_Institution :
State Key Lab. of Integrated Optoelectron., Inst. of Semicond., Beijing, China
Abstract :
A vertical grating coupler on silicon-on-insulator substrates has been designed and demonstrated. The light from a vertical fiber can be coupled in and split equally into two arms with the fiber placed in the grating center. An optical combiner is used to collect the transmission from the two arms. The measured peak coupling efficiency is 37%. Our device can also function like a Mach-Zehnder interferometer. In a device with an arm difference of 30 μm, the normalized transmission spectra of 20-nm free spectral range and more than 12-dB extinction ratio at 1567 nm are obtained.
Keywords :
Mach-Zehnder interferometers; diffraction gratings; optical couplers; optical design techniques; silicon-on-insulator; CMOS; Mach-Zehnder interferometer; Si; efficiency 37 percent; extinction ratio; free spectral range; normalized transmission spectra; optical combiner; peak coupling efficiency; quasi Mach-Zehnder characteristics; silicon-on-insulator substrates; vertical grating coupler; wavelength 1567 nm; Couplers; Couplings; Fiber gratings; Gratings; Optical fiber couplers; Optical fiber devices; Gratings; interference; silicon-on-insulator (SOI) technology; waveguide couplers;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2012.2234099
