Gallium-arsenide deep-center laser

In a novel approach to “thresholdless” lasers, we have developed a new growth technique for self-assembled deep centers in the technologically important semiconductor gallium-arsenide. Here we demonstrate the first gallium-arsenide deep-center laser. These lasers, which intentionally utilize gallium-arsenide deep-center transitions, exhibit a threshold of less than 2 A/cm2 in continuous-wave mode at room temperature at the important 1.54 μm fiber-optic wavelength. This threshold is much lower than for bandgap transitions in conventional bulk semiconductors. It is significant that this first demonstration of broad-area laser action was accomplished with electrical injection, and not merely optical pumping, as is usual for a new material.