Single-mode lasing in a coupled twin circular-side-octagon microcavity

Abstract

We demonstrate the curvature of coupled twin circular-side-octagon microcavity (TCOM) lasers as the degree of freedom to realize manipulation of mode quality (Q) factor and lasing characteristics. Numerical simulation results indicate that mode Q factors varying from 104 to 108, wavelength intervals of different transverse modes, and mode numbers for four-bounce modes can be manipulated for five different deformations. Global mode distributes throughout coupled microcavity with mode Q factor around the order of 104 or 105. Four-bounce modes lase with injection currents applied single microcavity. By pumping both microcavities simultaneously, single-mode lasing for global modes with side mode suppression ratios (SMSRs) of 30, 32, 32, 31, and 36 dB is achieved at the deformation of 0, 0.5, 1, 1.5, and 2 with four-bounce modes suppressed, respectively. Moreover, the linewidths less than 11 MHz for the single mode are obtained with the deformation of 2. The results show that the lasing modes can be efficiently manipulated considering variable curvature for TCOM lasers, which can promote practical applications of microcavity lasers.

Optically pumped wavelength-tunable lasing from a GaN beam cavity with an integrated Joule heater pivoted on Si

“…In the past years, tremendous progress has been made in the realization of wavelength-tunable lasers. For example, static wavelength tailoring has been realized in specially designed cavities such as compound cavities, [16,17] cavities with a distributed Bragg reflector [18] and coupled [19][20][21] or asymmetric cavities. [12,22] Apart from static wavelength tuning, GaN cavity lasers also exhibit the potential for excellent dynamic wavelength operation due to their optical-electrical characteristics, such as a high piezoelectric coefficient, [23] high electro-optical coefficient [24] or high thermo-optical coefficient.…”