A 1.55-μm semiconductor-optical fiber ring laser

Abstract

We demonstrate the first semiconductor-optical fiber ring laser. The laser uses an InGaAsP traveling wave optical amplifier as the gain medium and a 1-m length of highly birefringent fiber as the feedback loop. Output coupling is provided by a fiber directional coupler. The highly birefringent fiber is used as an intracavity wavelength filter, enabling single-frequency oscillation with a narrow linewidth at a wavelength near 1.55 μm.