Er3doped

Er3+-doped materials are optical media in which trivalent erbium ions (Er3+) substitute into a glass or crystal host to create active gain centers. The Er3+ ion has partially shielded 4f electrons, producing sharp optical transitions with emissions in the infrared, most notably near 1.55 micrometers.

The principal lasing and amplification transition is 4I13/2 to 4I15/2, yielding light around 1550 nm, which coincides with the low-loss window of silica fibers. Pumping commonly occurs at around 980 nm or 1480 nm to populate the 4I13/2 level, from which stimulated emission occurs.

Common hosts include silica in optical fibers, and crystalline materials such as Er:YAG, as well as fluoride-based glasses like ZBLAN and phosphate glasses. Doping levels range from tens to thousands of parts per million in glasses and up to several atomic percent in crystals, with trade-offs between gain and concentration quenching.

Er3+-doped materials are used in telecommunications as erbium-doped fiber amplifiers and in solid‑state lasers, with Yb3+ co-doping often employed to improve pumping efficiency. Performance depends on host phonon energy, site symmetry, and concentration, influencing absorption/emission cross sections and lifetimes.