Analysis of Mode Quality Factors for Equilateral Triangle Semiconductor Microlasers with Rough Sidewalls

The eigenmode characteristics for equilateral triangle resonator (ETR) semiconductor microlasers are analysed by the finite-difference time-domain technique and the Padé approximation. The random Gaussian correlation function and sinusoidal function are used to model the side roughness of the ETR. The numerical results show that the roughness can cause the split of the degenerative modes, but the confined modes can still have a high quality factor. For the ETR with 3 μm side length and the sinusoidal fluctuation, we can have the quality factor of 800 for the fundamental mode in the wavelength of 1500 nm, as the amplitude of roughness is 75 nm.