Fig. 1. Structural diagram of polarization-independent two-dimensional grating

Fig. 2. Reflectivity of PITDG and DBR. (a) Reflectivity of PITDG under different polarizations; (b) reflectivity comparison of PITDG and DBR

Fig. 3. Effects of duty cycle and period on reflectivity of PITDG. (a) Duty cycle; (b) period

Fig. 4. Three-dimensional structure of PIWT VCSEL

Fig. 5. Gain spectrum of quantum well

Fig. 6. Effect of air gap on lasing wavelength