Title :
Single-mode ultra-short quantum-cascade microlasers with deeply etched Bragg-mirrors
Author :
Hofling, S. ; Senfert, J. ; Reithmaier, J.P. ; Forchel, A.
Author_Institution :
Tech. Phys., Wurzburg Univ., Germany
Abstract :
Quantum-cascade (QC) microlasers with monolithically integrated semiconductor-air Bragg-mirrors based on GaAs were fabricated and investigated. In this paper we report the device properties of QC microlasers with strongly reduced cavity lengths and improved temperature properties. Based on a three-quantum well (3QW) active region design, the cavity length could be reduced from 180 μm to about 100 μm and based on a bound-to-continuum (BTC) active region design down to 50 μm. The devices were fabricated with an improved single etch step fabrication process, where the contact area is insulated with MgO to minimize leakage current. The ridge waveguide geometry and the Bragg-mirrors are defined separately by optical and electron-beam lithography, respectively.
Keywords :
electron beam lithography; gallium arsenide; high-speed optical techniques; integrated optics; leakage currents; magnesium compounds; micromirrors; optical fabrication; quantum cascade lasers; ridge waveguides; GaAs; MgO; bound-to-continuum active region design; deep etching; electron-beam lithography; leakage current; monolithically integrated semiconductor-air Bragg-mirrors; quantum-cascade microlasers; ridge waveguide geometry; three-quantum well active region design; Etching; Gallium arsenide; Insulation; Laser modes; Optical device fabrication; Power generation; Quantum cascade lasers; Semiconductor lasers; Temperature dependence; Threshold current;
Conference_Titel :
Lasers and Electro-Optics Europe, 2005. CLEO/Europe. 2005 Conference on
Print_ISBN :
0-7803-8974-3
DOI :
10.1109/CLEOE.2005.1567925
