Fig. 1. Cross-section schematic diagram of the surface grating VCSEL

Fig. 2. SEM images of the surface grating, which with a period of 700 nm, a duty cycle of 0.5, and an etching depth of about 60 nm. The diameter of the grating area is 5 μm

Fig. 3. Mirror loss varies with the etching depth of the grating

Fig. 4. Polarization test system

Fig. 5. Polarization-resolved light-current characteristics of ordinary VCSEL

Fig. 6. (a) Far-field characteristics, (b) Polarization-resolved P-I curve, (c) Polarization-resolved spectrum, and (d) The distribution of polarization states in the polar coordinate plane of the basic transverse mode surface grating VCSEL

Fig. 7. (a) Polarization-resolved P-I curve, (b) Polarization-resolved spectrum, and (c) Distribution of polarization states in the polar coordinate plane of a multi-transverse mode surface grating VCSEL

Fig. 8. Polarization-resolved P-I curves of surface grating VCSELs in different directions