Photonic bandgap defect laser

We form a microcavity laser using two-dimensional photonic crystals embedded in a half wavelength thick waveguide. Modes localized to a single defect in the photonic crystal can be theoretically shown to have mode volumes as small 2(λ/2n)³ and near unity spontaneous emission coupling factors. The flexibility in design of the photonic crystal enables one to tailor the device for vertical emission or for coupling into an in-plane waveguide. These type of devices may be useful for high density, low threshold optical sources in compact optical systems. The added versatility in being able to etch the laser cavity may also help develop low threshold laser sources in material systems in which high index contrast epitaxial mirrors do not exist. The defect laser cavities were formed in the InGaAsP material system in order to reduce the non-radiative surface recombination rate. The active region consists of four quantum wells (QW) designed for 1.55 μm peak emission at room temperature