Gain-dependent polarization properties of vertical-cavity lasers

Includes bibliographical references.We show that the partitioning of power into the two orthogonal eigen polarizations of infra-red gain-guided vertical-cavity lasers depends upon the relative spectral overlap of the nondegenerate polarization cavity resonances with the laser gain spectrum. Furthermore, at the condition where the polarization resonances and the peak laser gain are aligned, abrupt switching of power between the eigen polarizations is observed as the gain sweeps through the polarization resonances. The gain-dependence of the polarization requires spectral splitting between the eigen polarizations, which is found to be strongly influenced by local strain. The polarization of the fundamental and higher-order spatial modes can be selected and maintained for all InGaAs vertical-cavity lasers in a wafer simply by employing a 20 nm or greater blue-shift offset of the peak laser gain relative to the cavity resonances.The work performed at Sandia National Laboratories is supported by the U. S. Department of Energy under contract No. DE-AC04-94AL85000

Reconfigurable binary optical routing switches with fan-out based on the integration of GaAs/AlGaAs surface-emitting lasers and heterojunction phototransistors

Includes bibliographical references.The design, fabrication, and experimental demonstration of dynamically reconfigurable binary optical switches based on the integration of GaAs/AlGaAs vertical-cavity surface-emitting lasers and heterojunction phototransistors are reported. These new monolithic optical switches can perform spatial routing and optical amplification functions on input optical data with a fan-out of two, and can be programmed using simple voltage control. The 1 × 2 and 2 × 2 devices provide the basis for a high performance, two-dimensional optical switching fabric with electrical interfaces for optical switching and interconnection networks.The work at UNM was supported by Rome Laboratories (Griffiss AFB), the Advanced Research Projects Agency-MTO, and the Air Force Office of Scientific Research (Bolling AFB). The work performed at Sandia was supported by DOE Contract No. DE-AC04-76DP00789

Current injection GaAs/AlGaAs quantum wire lasers fabricated by cleaved edge overgrowth

We report the operation of quantum wire (QWR) semiconductor diode lasers fabricated by cleaved edge overgrowth. The active region in these index guided lasers consists of 15 QWRs formed at the right angle intersection of 15 [001] oriented quantum wells (QWs) each 7 nm wide, with a single 7-nm-wide QW grown along the [110] direction. Doping with Be and Si in the two orthogonal growth directions leads to the formation of a linear p-n junction in which the QWRs are embedded. Efficient current injection into the wires is demonstrated by the almost complete suppression of optical emission from QW states as well as by threshold currents as low as 0.4 mA for uncoated devices at 4.2 K