Project looks at use of fibre lasers in particle accelerators

Scientists from the Optoelectronics Research Centre (ORC) at Southampton University are part of an international project investigating the use of fibre lasers in particle accelerator technologies.

According to the university, laser particle acceleration is affected by two main issues — namely efficiency and repetition rates — because lasers used at present consume too much power, and can only produce the required ultra-fast laser pulses around once per second to produce acceleration.

For many applications needing high repetition rates — particle acceleration, X-ray and gamma ray generation — this makes the use of lasers economically unacceptable and impairs the spread of laser applications in science, material science, environment, medicine and energy.

However, the university believes fibre lasers may help to resolve this issue.

Fibre lasers can operate at very high average powers because of their ability to manage the heat generated by laser action.

This allows the laser to produce pulses many thousands of times per second, allowing particle acceleration at high repetition rates necessary for real-world applications.

Fibres should also improve the overall power efficiency of suitable lasers by a factor of a thousand, making them more economically feasible for experiments.

Ultra-fast fibre lasers, however, can produce only lower energy pulses because of optical non-linearities in the fibre medium, so do not have the requirement for high-energy physics.

The International Coherent Amplification Network (ICAN), a new EU-funded project, aims to harness the efficiency, controllability, and high-average-power capability of fibre lasers to produce high-energy, high-repetition-rate pulse sources. This will be achieved through a novel laser system, which combines the output of thousands of pulsed fibre lasers.

In a statement, ORC’s Dr Bill Brocklesby, project manager of ICAN, said: ‘High-energy ultra-fast lasers have already been demonstrated but the challenge to produce high-energy ultra-fast pulses at high rates is a specialty for the ORC.’

The ICAN project, which will last 18 months, has four main laboratories involved: ORC at the University of Southampton; Ecole Polytechnique, Paris; the Fraunhofer Institute for Applied Optics and Precision Engineering (Fraunhofer IOF); and CERN, the European Organisation for Nuclear Research.

It also involves a large number of worldwide partners from the laser, fibre and high-energy physics communities and industry.