High-performance strain-compensated InGaAs-GaAsP-GaAs (lambda=1.17 mu m) quantum-well diode lasers

This letter reports studies on highly strained and strain-compensated InGaA s quantum-well (QW) active diode lasers on GaAs substrates, fabricated by l ow-temperature (550 degreesC) metal-organic chemical vapor deposition (MOCV D) growth. Strain compensation of the (compressively strained) InCaAs QW is investigated by using either InGaP (tensile-strained) cladding layer or Ga AsP (tensile-strained) barrier layers, High-performance lambda = 1.165 mum laser emission is achieved from InGaAs-GaAsP strain-compensated QW laser st ructures, with threshold current densities of 65 A/cm(2) for 1500-mum-cavit y devices and transparency current densities of 50 A/cm(2). The use of GaAs P-barrier layers are also shown to significantly improve the internal quant um efficiency of the highly strained InCaAs-active laser structure. As a re sult, external differential quantum efficiencies of 56% are achieved for 50 0-mum-cavity length diode lasers.