Petawatt and exawatt class lasers worldwide

Rory Penman and Colin Danson

An international team of scientific experts has gathered to examine the current status of ultra-high-powered lasers around the world and look to the future to predict what the next generation of laser systems will offer. The culmination of their work is a major review paper 'Petawatt and Exawatt Class Lasers Worldwide', which looks at the historical context of this technology, its current and future use, and direction.

These ultra-high power lasers are capable of creating some of the most extreme conditions found in our solar system, if only for a tiny fraction of a second. They are used for understanding fundamental physics and producing secondary sources such as x-rays, electrons, protons and neutrons.

The paper takes a geographical tour of Asia, Europe and North America documenting operational facilities and those under construction. This is followed by a focus on future technologies where the authors have identified two main laser development streams: ultra-high-power and high-average-power. The first of which describes how scientists will produce exawatt class lasers, whilst the latter looks at how we can produce petawatt pulses at repetition rates at and beyond kHz repetition rates. The paper then concludes with a view to the future and what grand challenges need to be overcome in order to achieve the ultra-high-power and high-average-power lasers.

These two development streams are both working on some really exciting laser physics at the moment:

In the ultra-high power stream teams of scientists all over the world are working towards smashing current power records. Using the OPCPA (Optical Parametric Chirped Pulsed Amplification) technique a team at SIOM, China are planning to deliver 100 petawatts in 2023. This is particularly impressive when you consider that in the year 2000 scientists using the OPCPA technique were only capable of delivering 1.6 terawatts; that’s a 62,500 times increase in output power in just 23 years.

In delivering high repetition rate systems at ultra-high powers the review paper identifies those milestone events: the BELLA facility producing petawatt pulses at 1 Hz in 2013; and the HAPLS laser producing petawatt pulses at 10 Hz in 2018. This incredible progress will have to continue in the next decade to deliver the kHz petawatt class lasers of the future for industrial / medical applications.

Geographic distribution of high-peak-power lasers (top). Diameter of circle is logarithmically proportional to peak laser power and circle colour is chosen for graphical clarity. Evolution of high-peak-power lasers ( > 100 GW) in the world over the last fifty years (bottom).