All-fiber coherent Combining of Er-doped amplifiers via refractive index control in Yb-doped fibers by two-wavelengths optical signal

摘要

Here we report a coherent combining of two 500- mW EDFAs operating at 1550nm with a dynamical phase control provided either by one low-power laser diode at 980nm alone or in combination with a laser at 1060nm both stimulating electron transitions in an Yb-doped optical fiber. Two wavelengths scheme improves the dynamical range and the response time of the phase control loop.