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Pulsed operation at a wavelength of 1.27 μm from metamorphic ridge-waveguide (RWG) InGaAs quantum well lasers on GaAs substrates using an alloy graded buffer, grown by molecular beam epitaxy, is demonstrated. Laser performance is anisotropic along the two orthogonal <1±10> directions with lower threshold currents along the <1-10> direction. Post-growth rapid thermal annealing further reduces threshold currents. For 4 μm-wide RWG lasers, minimum threshold current densities are 1-2.5 kA/cm2 for cavity lengths 0.6-1.5 mm.