Abstract

Short, single-frequency Er³⁺-doped fiber lasers using photorefractive grating feedback¹ are emerging as an interesting alternative to DFB diode lasers for use in high-capacity WDM communication systems, as well as in LIDAR, fiber-optic sensor and spectroscopy applications. Fiber lasers have low noise and kHz linewidths, are temperature insensitivity and fiber compatible, and are scalable to high output powers. By co-doping the Er³⁺-doped fiber with Yb³⁺, and thus increasing the pump absorption at 980 nm, we have recently shown^2,3 that the over-all slope efficiency of such short (cms) single-frequency DBR fiber lasers can be increased to 22%, i.e., by two orders of magnitude, to give a diode- pumped output power of 19 mW.

© 1994 Optical Society of America