Fig. 1. Schematic diagram of GaSb-based ICL epilayers

Fig. 2. Morphology and characteristics of DFB ICLs^{［20，22，24-25］}

Fig. 3. Lateral metal grating DFB ICLs^{［26，31-32，37］}

Fig. 4. Lateral grating DFB ICLs^［44-45］

Fig. 5. Combined grating DFB ICL^［46］

Fig. 6. Second-order GaSb surface grating DFB ICLs^［48］

Fig. 7. 2nd DFB ring ICL^［53］

Fig. 8. Interband cascade vertical cavity surface emission laser^［58］

Fig. 9. ICVCSEL with wafter-bonded GaAs/AlGaAs bottom DBR^［60］

Fig. 10. α-DFB lasers^［62］

Fig. 11. 2D PCDFB laser^{［65，67］}

Fig. 12. Design of surface emitting PCDFB laser with a hexagonal lattice^［71-72］

Fig. 13. SE PCDFB laser with a hexagonal lattice^［73］

Fig. 14. PCDFB QCLs with different grating locations

Fig. 15. Edge emitting PCDFB ICLs^［76］

Fig. 16. Double-lattice photonic-crystal resonator^{［80-81，83］}.