GaSb-based lasers with two-dimensional photonic crystal mirrors

摘要

We present the realization of two-dimensional (2D) photonic crystals (PhCs) on the GaSb material system. An electron cyclotron resonance reactive ion etch process using Cl-2/Ar allows the fabrication of PhCs covering air fill factors of f = 20%-50%, lattice periods of a = 400-500 nm and aspect ratios of 5:1. Quality and reflectivity of these structures are evaluated by incorporating the PhCs as high reflective back mirrors in GaSb-based ridge waveguide lasers with cavity lengths between 200 and 1100 mu m with the front facet as cleaved. The shortest devices show remarkable threshold currents below 12 mA and efficiencies of 0.23 W A(-1), yielding a maximum output power of almost 19 mW, proving the applicability of the chosen approach to numerous further concepts based on 2D PhCs on the GaSb material system.