Strong optical emissions from two-dimensional metal photonic crystals with semiconductor multiple quantum wells

We investigated two-dimensional (2D) metal photonic crystals (PhCs) with semiconductor multiple quantum wells as an active material. The 2D metal PhCs were fabricated using only a lift-off process. The lift-off process leads to a simpler fabrication process than the one for conventional PhCs and avoids any process damage induced by dry etching. The 2D metal PhCs exhibited clear photonic band effects: (1) photoluminescence (PL) peak positions changed depending on the lattice constant and (2) the PL intensity from 2D metal PhCs was higher than that without 2D metal PhCs. These effects are suitable for fabricating light-emitting diodes with a high external quantum efficiency. PL intensity depending on PL excitation power revealed slightly improved luminescence efficiency than the sample without 2D metal PhCs.