The Research of Nanophotonic Grating Vertical Coupling
In this paper, we discuss the theory research and testing methods of a grating coupler. The grating coupling efficiency of parameters and the corresponding theoretical simulation was studied systematically. Meanwhile, the coupling efficiency in theory can be improved to 76% using an optimized grating design. The fabrication of the couplers in silicon-on-insulator is focusing on ion beam method (FIB). Using the tunable NewFocus laser with an adjustable extent of 1520~1570nm as the sources, Si waveguide grating is achieved vertical coupler through coupling a single-mode fiber with the diameter of 10.4. In the experiment, when the input wavelength is 1550nm, the maximum coupling efficiency is measured approximately 31% and 1 dB bandwidth is approximately 30 nm.
Xiaoming Sang, Pengcheng Wang, Liqun Ai, Yungang Li and Jinglong Bu
D. F. Cui et al., "The Research of Nanophotonic Grating Vertical Coupling", Advanced Materials Research, Vols. 284-286, pp. 711-716, 2011