Department of Innovative and Engineered Materials;
Tokyo Institute of Technology;
Yokohama 226-8503;
Japan;
Center of Advanced Instrumental Analysis;
Kyushu University;
Kasuga 816-8580;
Japan;
Department of Physics;
Chalmers University of Technology;
Gothenburg 41296;
Sweden;
cathodoluminescence; plasmonic nanopore; short-range order; surface plasmon; transmission electron microscopy;