Tunable sampled-grating DBR lasers using quantum-well intermixing

Widely tunable lasers are key components for wavelength division multiplexing fiber optic networks. They reduce cost in sparing, enable dynamic networking applications, and present opportunities for future monolithically integrated wavelength division multiplexing components. The sampled-grating distributed Bragg reflector (SGDBR) laser is ideal for these purposes. The authors present a centered quantum-well SGDBR laser which uses quantum-well intermixing in order to improve device characteristics over previous designs. The mode overlap is improved by 50% over the offset quantum-well design, improving the modal gain. Current injection tuning in the intermixed material is demonstrated for the first time; the maximum modal group index change was measured to be 1%.