Fig. 1. Structure diagrams of GaN-PCSEL. (a) Diagram of structural parameters; (b) top view of triangular lattice of TiO₂-PhC layer

Fig. 2. Energy band diagram of designed structure

Fig. 3. Reflection and transmission spectra of porous-GaN/GaN DBRs

Fig. 4. Surface field distributions for mode 1 and mode 2, and variations of resonant wavelength, confinement factor of photonic crystal layer, active region confinement factor, and cavity quality factor with h and t. (a)(b) Surface field distributions for mode 1 and mode 2; (c)‒(j) variations of resonant wavelength, confinement factor of photonic crystal layer, active region confinement factor, and cavity quality factor with h and t

Fig. 5. Light field distributions calculated by different methods. Light field distributions of (a) mode 1 and (b) mode 2 in each layer calculated by RCWA method; light field distributions of (c) mode 1 and (d) mode 2 in xz plane calculated by FDTD; light field distributions of (e) mode 1 and (f) mode 2 in xy plane calculated by FDTD

Fig. 6. Relationship among vertical loss, slope efficiency, and interference phase. (a)(b) Relationship between αv_DBRand θ for both modes; (c)(d) relationship between ηSE and θ for both modes

Fig. 7. Comparison of slope efficiencies of PCSEL with DBR structure and PCSEL with porous GaN cladding layer