Fiber laser oscillators and amplifiers

Summary form only given. Although erbium-doped fiber amplifiers at 1.5 /spl mu/m in silica have been outstandingly successful, other hosts such as fluorides or tellurites have been studied because of their broader gain lines, which could make them advantageous for WDM systems. The use of other hosts doped with other rare earths are being considered for other wavelengths, particularly the near-IR 3- to 5-/spl mu/m region. The choice of a glass host for a given rare earth transition depends on the competition between radiative transition probabilities and the quenching phonon relaxations.