Gain-coupled distributed-feedback GaInAs-GaAs laser structures defined by maskless patterning with focused ion beams

First-order periodic gain modulation in GaInAs-GaAs laser structures has been realized by maskless focused ion-beam implantation. The structures were implanted with Ga/sup +/-ions at an ion energy of 130 keV and a line dose of 1*10/sup 7/ 1/cm. The periodicity of the gratings was designed for laser operation at 77 K and room temperature. With optical pumping we have observed single-mode laser operation due to the distributed feedback effect at wavelengths between 849 mn and 944 mn at 77 K (grating periods between 124 and 140 nm) and between 954 nm and 1005 mn at room temperature (grating periods between 140 and 148 nm).<
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