Fig. 1. Structural diagram of coupled-circular micro-cavity laser

Fig. 2. Laser characteristics at 20, 400, and 1250 h. (a) Output spectra at I＝100 mA; (b) P-V-I curves

Fig. 3. Laser output spectra at 400 h. (a) Detailed spectra at I＝130，135，140，145，150 mA; (b) spectrum at I＝130 mA

Fig. 4. Laser output power and threshold current versus time during aging test. (a) Output power at I＝100 mA; (b) threshold current

Fig. 5. Abnormal change analysis of output power and threshold current of device. (a) Laser output spectra at I＝100 mA; (b) temperature of active region versus injection current with lasing wavelength versus injection current shown in inset; (c) temperature versus time at I＝100 mA