Influence of Etching Slope on Two-Dimensional Photonic Crystal Slab Resonators

Myung-Ki Kim, Jin-Kyu Yang, Yong-Hee Lee and In-Kag Hwang

J. Korean Phys.Soc. 50,1027 [doi: 10.3938/jkps.50.1027 | PDF Download]

The influence of the etching slope on the Q-factors in two-dimensional (2D) photonic crystal (PhC) slab resonators is studied. The Q-factor of a three-lattice-long modified linear resonator was measured to be much smaller than the theoretical prediction. Through a finite-difference time-domain (FDTD) simulation, we confirmed that the Q-factor decreases with etching slope. The horizontal loss becomes dominant when the angle of the etching slope exceeds one degree. This loss originates from the coupling into propagating TM-like modes.