HIGH-POWER DIRECTIONAL EMISSION FROM MICROLASERS WITH CHAOTIC RESONATORS

High-power and highly directional semiconductor microcylinder lasers b ased on an optical resonator with deformed cross section are reported. In the favorable directions of the far-field, a power increase of up to three orders of magnitude over the conventional circularly symmetri c lasers was obtained. A ''bow-tie''-shaped resonance is responsible f or the improved performance of the lasers in the higher range of defor mations, in contrast to ''whispering-gallery''-type modes of circular and weakly deformed lasers. This resonator design, although demonstrat ed here in midinfrared quantum-cascade lasers, should be applicable to any laser based on semiconductors or other high-refractive index mate rials.