Lasing oscillation in a three-dimensional photonic crystal nanocavity with a complete bandgap

We demonstrate lasing oscillation in a three-dimensional photonic crystal nanocavity. The laser is realized by coupling a cavity mode, which is localized in a complete photonic bandgap and exhibits the highest quality factor of ~38,500, with high-quality semiconductor quantum dots. We show a systematic change in the laser characteristics, including the threshold and the spontaneous emission coupling factor by controlling the crystal size, which consequently changes the strength of photon confinement in the third dimension. This opens up many interesting possibilities for realizing future ultimate light sources and three-dimensional integrated photonic circuits and for more fundamental studies of physics in the field of cavity quantum electrodynamics.Comment: 14 pages, 4 figure

Resonance-driven random lasing

4 pages, 4 figures.-- Supplementary material available at http://dx.doi.org/10.1038/nphoton.2008.102: Fig. 1: Ohm's law fit for photonic glass, Fig. 2: Two dyes photonic glass reference sample.A random laser is a system formed by a random assembly of elastic scatterers dispersed into an optical gain medium. The multiple light scattering replaces the standard optical cavity of traditional lasers and the interplay between gain and scattering determines the lasing properties. All random lasers studied to date have consisted of irregularly shaped or polydisperse scatterers, with a certain average scattering strength that was constant over the frequency window of the laser. In this letter we consider the case where the scattering is resonant. We demonstrate that randomly assembled monodisperse spheres can sustain scattering resonances over the gain frequency window, and that the lasing wavelength can therefore be controlled by means of the diameter and refractive index of the spheres. The system is therefore a random laser with an a priori designed lasing peak within the gain curve.The work was financially supported by the European Commission (EC) (LENS) under contract number RII3-CT-2003-506350, by the European Union (EU) through the Network of Excellence IST-2-511616-NOE (PHOREMOST), CICyT NAN2004-08843-C05, MAT2006-09062, the Spanish MEC Consolider-QOIT CSD2006-0019 and the Comunidad de Madrid S-0505/ESP-0200.Peer reviewe