A GaN nanorod and formation method. Formation includes providing a substrate having a GaN film, depositing SiNx on the GaN film, etching a growth opening through the SiNx and into the GaN film, growing a GaN nanorod through the growth opening, the nanorod having a nanopore running substantially through its centerline. Focused ion beam etching can be used. The growing can be done using organometallic vapor phase epitaxy. The nanopore diameter can be controlled using the growth opening diameter or the growing step duration. The GaN nanorods can be removed from the substrate. The SiNx layer can be removed after the growing step. A SiOx template can be formed on the GaN film and the GaN can be grown to cover the SiOx template before depositing SiNx on the GaN film. The SiOx template can be removed after growing the nanorods.