Cladding-pumped Tm~(3+)-doped Silica Fiber Laser with High Output Power and Good Beam Quality

A cladding-pumped thulium(Tm3 +)doped silica fiber laser with high output power and good beam quality has been demonstrated.The Tm3 +-doped fiber laser produced a maximum output power of 6.1 W at wavelength around 2 μm when the incident pump power was 30 W.The slope efficiency was about 55.6% and the threshold was 2.2 W.The beam quality factor M2X and M2Y were 1.26 and 1.32 respectively when the output power was 3.3W.