Square microcavity laser with an output waveguide is proposed and analyzed by the finite-difference time-domain (FDTD) technique. For a square resonator with refractive index of 3.2, side length of 4 microns, and output waveguide of 0.4-micron width, we have got the quality factors (Q factors) of 6.7*10^(2) and 7.3*10^(3) for the fundamental and first-order transverse magnetic (TM) mode near the wavelength of 1.5 microns, respectively. The simulated intensity distribution for the first-order TM mode shows that the coupling efficiency in the waveguide reaches 53%. The numerical simulation shows that the first-order transverse modes have fairly high Q factor and high coupling efficiency to the output waveguide. Therefore the square resonator with an output waveguide is a promising candidate to realize single-mode directional emission microcavity lasers.
© 2007 Chinese Optics Letters
(140.3410) Lasers and laser optics : Laser resonators
(140.3570) Lasers and laser optics : Lasers, single-mode
(140.4780) Lasers and laser optics : Optical resonators
(230.3990) Optical devices : Micro-optical devices
Wei Zhao and Yongzhen Huang, "Analysis of directional emission in square resonator lasers with an output waveguide," Chin. Opt. Lett. 5, 463-465 (2007)