Fig. 1. Simulation results of magnetic field distribution for the square microcavity unit and the microcavity array. (a) Mode Q factor versus wavelength for the square microcavity unit with four waveguides; (b) mode field distribution and enlarged view for 0th ASM and SM of the square microcavity unit with four waveguides; (c) mode Q factor versus wavelength for 2×4 microcavity array; (d) mode field distribution for the mode with highest Q in the 2×4 microcavity array

Fig. 2. Experimental results of laser array with current injection only for the upper square microcavity lasers. (a) SEM image of the 2×4 square microcavity laser array; (b) output power and voltage coupled to multi-mode fiber (MMF) versus continuous injection current in the upper lasers measured at port 1; (c) emission spectra collected by MMF from four ports independently at I_upper=30 mA; (d) enlarged spectra near 1534.13 nm corresponding to Fig. 2(c)

Fig. 3. Experimental results of the laser array with current injection only for the lower square microcavity lasers. (a) Emission spectrum map measured at port 2 when the injection current I_lower changes from 15 mA to 80 mA; (b) spectrum at the injection current I_lower=30 mA

Fig. 4. Experimental results of the laser array under simultaneous injection from the upper and lower rows of lasers. (a) Emission spectra collected by MMF at port 2 under I_lower=30 mA when I_upper increases from 0 mA to 85 mA; (b)-(d) spectra at the injection current I_upper=24 mA, 56 mA, and 75 mA under I_lower=30 mA