High power semiconductor laser injection-locking at 1.3 μm

The injection-locking properties of a high power antireflection coated 1.3-μm slave laser subjected to relatively low injection powers from a distributed feedback (DFB) laser and from a tunable external cavity laser have been investigated. Narrow linewidth operation (~40 kHz) was demonstrated and the tuning range within two slave modes (~10 GHz) and over the gain profile (~40 nm) was investigated. In addition, the tracking properties of the slave laser for both frequency and phase modulated injected light was evaluated at 1 Gb/s, in which the fidelity was judged from bit-error-rate measurements. The maximum locked power under 1 Gb/s frequency modulation was about 145 mW, limited by the available master power; approximately 300 μW was injected into the slave     

Growth and characterization of continuously graded index separateconfinement heterostructure (GRIN-SCH) InGaAs-InP long wavelengthstrained layer quantum-well lasers by metalorganic vapor phase epitaxy

A report is presented on the growth and characterization of the first InGaAs-InP-based graded-index separate-confinement-heterostructure (GRIN-SCH) strained quantum-well lasers operating near 1.47 μm. The structure features linearly graded InGaAsP waveguide layers for both optical and carrier confinement in a very narrow, strained quantum-well layers. The excellent structural quality of the active and waveguide regions has been confirmed by transmission electron microscopy (TEM) and secondary ion mass spectroscopy (SIMS) analysis results. Strained quantum-well lasers with well widths as narrow as 5-6 nm were fabricated with threshold current densities as low as 750 A/cm². Buried-heterostructure lasers based on strained quantum-well active lasers exhibit threshold currents as low as 10-15 mA with quantum efficiency of 70-80%. With antireflection coating on one side of the sample, the laser shows threshold current of 35 mA with highest output power of 160 mW     

Effect of thermionic electron emission from the active layer on theinternal quantum efficiency of InGaAsP lasers operating at 1.3μm

We have experimentally characterized the quantum efficiency in InGaAsP lasers operating at 1.3 μm. The observed reduction in external quantum efficiency with increasing temperature and increasing bias current is found to be caused almost entirely by a reduction of the internal quantum efficiency. The internal quantum efficiency is reduced approximately linearly with bias current in the temperature range investigated. The experimental results are well explained with a theoretical model based on thermionic emission of carriers out of the active region     

New 1.6 ?m wavelength GaInAsP/InP buried heterostructure lasers

1.6 ?m wavelength GaInAsP/InP buried heterostructure (b.h.) lasers were fabricated by a new process. The low threshold of 25 mA was obtained for a cavity length of about 300 ?m and stripe width of 3?5 ?m. Room temperature c.w. operation was also obtained with the threshold of 37 mA. Transverse single-mode operation up to more than three times the threshold was obtained.