Pulsed Fibre Lasers

This group is part of the Advanced Fibre Technologies & Applications Group

Fibre laser technology offers tremendous prospects for the development of compact, robust pulse sources capable of operating over a very wide range of pulse parameters spanning from the microsecond down to the femtosecond regime.

The ORC has been engaged in pulsed fibre laser development since the first demonstration of fibre lasers in the mid-1980s. Over this period it has produced numerous world first results most notably in the area of high energy Q-switched systems, passively mode-locked lasers, high average power pulsed systems and fibre laser pumped parametric devices.

By virtue of their excellent power handling characteristics and advances in both pump diode and fibre fabrication technology fibre lasers can now be made to reliably operate at kW average power levels, and are able to generate multi-mJ pulse energies. Consequently, fibre systems are now sufficiently powerful to be used in applications such as high-precision welding, cutting, and marking of metals and ceramics. Significantly, a number of car manufacturers now use laser welding to assemble vehicle bodies exploiting the high average powers that can be generated and accurately delivered to the workpiece. 

For processes in which peak power is critical the possibility for high average powers can be exploited to obtain high pulse repetition rates and thus greatly increased processing speeds. A key feature of fibre lasers is that the laser beams generated are of a much higher beam quality than competing technologies and so can be focused to a much smaller spot size, or used to provide substantial increases in working distance from the target. This opens up a host of new material processing possibilities, such as precision manufacturing of tiny precision components for body implants, and the direct writing of optical and electrical circuits.

In general terms our current research is focused on:

  • the development of ever more powerful pulsed lasers and amplifiers, both in terms of pulse peak power (>1GW) and average power (>300W)
  • tailoring of the pulse characteristics to suit the growing range of pulsed fibre laser applications e.g. laser marking, welding and cutting
  • nonlinearity and dispersion management in pulsed fibre laser systems
  • frequency conversion of pulsed fibre laser output to new wavelength ranges using external nonlinear elements (e.g. to the X-ray, UV and mid-IR)
  • the development of ever more reliable, practical and low cost systems

Copyright University of Southampton 2006