Efficient mid-infrared laser under different excitation pump wavelengths.

Abstract

A laser operating at 2.8μm in a lightly doped Er3+:SrF2 crystal is analyzed first for different excitation pump wavelengths: 972nm and 1532nm. A maximum output power of 814mW was obtained by a 972-nm commercial laser diode, and the corresponding slope efficiency was 30.4%. Laser emission under 1532-nm excitation was also achieved by efficient upconversion energy transfers. This could be an effective technique for realizing a compact and efficient upconversion laser capable of emitting in the mid-infrared regime.