Cavity-enhanced photonic crystal light-emitting diode at 1300 nm
We report direct evidence of enhanced spontaneous emission in a photonic crystal light-emitting diode (LED) at telecom wavelength (lambda similar to 1300 nm). This result is crucial to obtain an electrically driven single photon source with high extraction efficiency. This kind of devices can be used for different types of applications in emerging fields like quantum key distribution, quantum information technology as well as in fundamental studies on quantum electrodynamics. In this work we present a device which combines a photonic crystal nanocavity with InAs quantum dots (QDs) and an LED, leading to cavity-enhanced emission at telecom wavelengths under electrical injection. The fabrication process, based on e-beam lithography and additive and subtractive processes, is described in detail. A well-isolated emission peak at about 1300 nm from the PhC mode electrically pumped is obtained (Q similar to 4000), and the enhancement of the spontaneous emission rate (similar to 1.5 fold) is clearly evidenced by time-resolved electroluminescence measurements. (C) 2008 Elsevier B.V. All rights reserved.