13 European Molecular Beam Epitaxy [March 7-9. 2005, Grindelwald (Switzerland)]. Workshoposter
Self assembled wireson InP(001) nanostructures can potentially be used for the fabrication of lasers working at 1550 nmat Room Temperature. We present initial structures working LASER DEVICES at temperatures as high as 250K. Laser structures with 1 and 3 stacked layers of self-assembled InAs Quantum Wires(QWR) in the active region and SPSL(GaInAs)/(inP) as waveguide have been grown by molecular beam epitaxy (MBE) on InP(001) substrates. The QWR are formed after deposition of ~2 monolayers (ML) of InAs. The 20nm thick spacers between each layer of QWR are formed by the same SPS Lusedas waveguide. A control laser structure with three stacked layers of 7.5nm thick lattice matched GaInAs quantum wells has also been grown. PL measurements show emission associated with the QWR in the range 1370-2000nm. With these structures broad area lasers have been fabricated. The Laser devices have been characterized performing electroluminescence spectroscopy (EL) and light-current mesurements. The laser emission is observed at low temperature to 250K, with a density threshold current of 570A/cm2 per wires layer. More optimizations in the structures are necessary to obtain laser emission at room temperature. To optimize the optical properties of the laserwaveguide, we calculate the optical confinement factor as a function of the number of periods of (GaInAs)/(InP)with different x and y values. Also, we calculate the energy minibands of this superlattices in order to study the confinement of the carriers into the QWR.
This work has been supported by the European Commission Growth program NANOMAT project, contract no. G5RD-CT-2001-00545 and SANDIE Network of Excellence within the 6 FP Contract No. NMP4-CT-2004-500101, by Spanish MCYT under NANOSELF project TIC 2002-04096-C03-03.