1：Experimental Design and Method Selection:

The study involved the growth of various InGaN/GaN pn-junction nanocolumn arrays arranged in a triangle-lattice on the same substrate while changing the nanocolumn diameters (Dn-GaN) of the underlying n-side GaN region under the lattice constant (L) of 340 nm. The periodic arrangement of nanocolumns leads to a photonic crystal effect.

2：Sample Selection and Data Sources:

The nanocolumn arrays were grown on metal-organic-chemical-vapor-deposition (MOCVD)-grown GaN templates on c-face sapphires.

3：List of Experimental Equipment and Materials:

The growth was performed using radio frequency (RF)-plasma-assisted molecular beam epitaxy (RF-MBE). The photoluminescence (PL) spectra were evaluated at room temperature with micro-PL measurements under 405-nm wavelength InGaN laser diode excitation.

4：Experimental Procedures and Operational Workflow:

The growth was interrupted at the top of the n-GaN nanocolumn to measure the nanocolumn diameter (Dn-GaN). Subsequently, λB was evaluated after the growth of the InGaN/GaN active and p-GaN cladding layers on the n-GaN nanocolumn arrays.

5：Data Analysis Methods:

The normalized frequency at the photonic band edge (L/λB) was plotted as a function of (Dn-GaN/L)2.