Enhancement of room temperature sub-bandgap light emission from silicon photonic crystal nano cavity by Purcell effect

We report the enhancement of sub-bandgap photoluminescence from silicon via the Purcell effect. We couple mission from silicon, which is believed to be due to hydrogenin corporation in to the lattice, to a photonic crystal (PhC) nanocavity. We observe an up to 300-fold enhancement of the emission at room temperature at 1550 nm, as compared to an unpatterned sample, which is then comparable to the silicon band-edge emission. We discuss the possibility of enhancing this emission even further by introducing additional defects by ion implantation, or by treating the silicon PhC nano cavity with hydrogen plasma. (c) 2011 Elsevier B.V. All rights reserved.