Highly directional emission from few-micron-size elliptical microdisks

Few-micron-sized elliptically deformed InGaAsP-InP microdisk lasers are fabricated and highly directional emissions are observed along the direction perpendicular to the surface of highest curvature. As the size of the elliptical microdisk is reduced, both the azimuthal angular spreading and the number of lobes become smaller. The improved directionality of the smaller structure is attributed to the enhanced tunneling loss at the high curvature surfaces. The far-field radiation is linearly polarized. Charge-coupled-device images confirmed the existence of strong near-field emission in the vicinity of high curvature surfaces. (C) 2004 American Institute of Physics.