Small-signal gain measurements for highly doped and co-doped Er3+:YAG at 2.936μm

•Direct small-signal gain measurements for Er3+:YAG laser rods at ∼3μm are given.•The small-signal gain ranges from 0.005 cm−1 to 0.027 cm−1 for Er3+:YAG.•The Eu co-doped rods have gains in the range of 0.025 cm−1 to ∼0.037cm−1.•The Pr co-doped rods have gains (0.0001 cm−1 to 0.001 cm−1).•The system is biologically and technologically important due to H2O absorption located near 3μm.

Direct small-signal gain measurements have been made for a 50% doped Er3+:YAG rods for the 2.936μm wavelength. We also provide gain measurements for 55% Er3+:YAG and co-doped 55% Er3+:YAG rods.Erbium doped solid-state lasers are typically used in a flash-pumped configuration, where the gain dynamics is highly dependent on the pump–pulse length. In this paper we have reported the small-signal gain over the pulse duration, along with average small-signal gain, so as to provide the laser-engineer with data to efficiently design the mid-IR laser system.