Design consideration and performance of high-power and high-brightness InGaAs-InGaAsP-AlGaAs quantum-well diode lasers (lambda=0.98 mu m)

In this paper, we conduct a theoretical analysis of the design, fabrication , and performance measurement of high-power and high-brightness strained qu antum-well lasers emitting at 0.98 mum, The material system of interest con sists of an Al-free InGaAs-InGaAsP active region and AlGaAs cladding layers . Some key parameters of the laser structure are theoretically analyzed, an d their effects on the laser performance are discussed. The laser material is grown by metal-organic chemical vapor deposition and demonstrates high q uality with low-threshold current density, high internal quantum efficiency , and extremely low internal loss. High-performance broad-area multimode an d ridge-waveguide single-mode laser devices are fabricated. For 100-mum-wid e stripe lasers having a cavity length of 800 mum, a high slope efficiency of 1.08 W-A, a low vertical beam divergence of 34 degrees, a high output po wer of over 4.45 W, and a very high characteristic temperature coefficient of 250 K were achieved. Lifetime tests performed at 1.2-1.3 W (12-13 mW/mum ) demonstrates reliable performance. For 4-mum-wide ridge waveguide single- mode laser devices, a maximum output power of 394 mW and fundamental mode p ower up to 200 mW with slope efficiency of 0.91 mW/mum are obtained.