High-pulse-energy, actively Q-switched Tm3+,Ho3+ -codoped silica 2 microm fiber laser.

A diode-pumped Q-switched Tm(3+),Ho(3+)-codoped double-clad silica fiber laser is reported providing average powers of up to 12.3 W at 2072.7 nm and stable pulse widths of only 45 ns and repetition rates in the range 10-100 kHz.

Theory and optimization of hollow ducts.

Hollow ducts compressing and homogenizing the emission of laser diode arrays are cheap, low weight alternatives to lens ducts. An analytic model is presented describing hollow ducts including internal reflection losses, which is useful in optimizing these devices, especially in determining the optimum length for maximum transmission efficiency. As an example, a gold coated duct is presented showing high transmission efficiencies of >90% comparable to lens ducts.

High-pulse-energy actively Q-switched Tm3+-doped silica 2 microm fiber laser pumped at 792 nm.

A diode-pumped Q-switched Tm(3+)-doped double-clad silica fiber laser is reported providing average powers of up to 30 W at pulse widths of only 41 ns and repetition rates in the range of 10-125 kHz. Up to 270 microJ pulse energy was produced. Amplified spontaneous emission (ASE) buildup limits the maximum peak power, and the pump power and average output power at the point of ASE induced clamping were found to depend linearly on the repetition rate.