High-power indium phosphide semiconductor lasers

Several important applications in optical communications require high power fiber coupled laser sources operating at 1.3 /spl mu/m, 1.48 /spl mu/m and 1.55 /spl mu/m. Semiconductor diode lasers for these wavelengths can be fabricated using the InP/lnGaAsP material system. High power operation requires careful selection of the active region, p and n doping and the lateral waveguide structure. Additionally, distributed feedback (DFB) lasers require appropriate choice of grating feedback. High power, narrow linewidth and low noise single mode diode laser sources operating at 1.3 /spl mu/m and 1.55 /spl mu/m wavelengths have applications in cable television transmission systems, microwave photonics, interferometric sensors and as an alternative to diode-pumped solid state lasers. High output power is desirable to overcome losses in external modulators and for large scale distribution systems. It is particularly important for 1.3 /spl mu/m applications as reliable and efficient fiber amplifiers are not commercially available at this wavelength. 1.3 /spl mu/m DFB lasers with 440 mW chip power, over 150 mW fiber coupled power and 100 kHz linewidth have been demonstrated.