The emission of Er3+ at 1530 nm has attracted special attention in telecommunication applications. Because it is in the third fiber optic communication window . This emission is critical for information transfer in Er3+ doped fiber optical amplifiers and is often used in wavelength division multiplexing networks.
Er Yb phosphate laser glass with its excellent fluorescence properties and chemical stability, especially the ion exchange method can be used to make high gain per unit length, high output power, wide bandwidth, noise close to the quantum limit, independent of polarization of the integrated optical waveguide amplifier has attracted great attention, at the same pump power, the optimal length of phosphate-based fiber amplifier than the quartz glass-based fiber amplifier is shorter.
The main components of device are:
- Pump input
- signal input
- Pump/signal multiplexer
- Undoped silicate glass
- Power amplifier
- Er-doped phosphate glass
- Amplified signal output
In the Er and Yb co-doping system, Yb absorbs most of the pump energy and quickly transfers it to the adjacent Er. The larger phonon energy in the phosphate glass matrix increases from 4I11/2–4I13 /2, the chance of transition, the energy is reversed from Er to Yb. Yb not only has a larger absorption cross section, but also a wider absorption band (800nm~1100nm). Therefore, glass fibers doped with Yb can expand the pump wavelength range. The pump light source is usually a laser diode.