Gemini creates 'ghostly mirrors' for high-power lasers
31 Jan 2023



Laser-driven ‘mirrors’ capable of reflecting or manipulating light have been produced using the CLF’s Gemini during research led by the University of Strathclyde, published in Nature Communications Physics.

Optics inside one of Gemini's target areas.

​Optics inside one of Gemini's target areas.

These 'mirrors', that exist for only a few picoseconds (less than 1/100,000,000,000th of a second), have the potential to be developed into a variety of plasma-based, high intensity-threshold optical elements. If used for laser optics, these mirrors could lead to a reduction in the footprint of ultra-high-power lasers.

Panorama photo of the optics inside one of Gemini's target areas.

Professor Dino Jaroszynski of Strathclyde's Department of Physics led the research. He said:

“High-power lasers are tools that enable research in many areas of medicine, biology, material sciences, chemistry and physics. Making high-power lasers more widely available would transform the way science is done.

This work significantly advances the state-of-the-art of high-power lasers by proposing new methods for creating optical elements. These are more compact and much more robust than existing optical elements, and also transient, which makes them unique.

The research group are planning for further proof-of-principle experiments to demonstrate the robustness and fidelity of the plasma optical elements. Part of this plan​ includes a follow-on experiment on Gemini in August 2023 to make 3-dimensional plasma photonic structures."

This research utilised the dual beam capabilities of Gemini to generate counter-propagating laser beams to produce layered plasma mirrors. Plasma is a fully ionised gas, like a soup of electrons and ions, and makes up the vast majority of the visible universe. By firing counter-p​ropagating laser beams at the plasma, electrons and ions are driven into a regular, layered structure. This structure is a high reflectivity mirror with a 'ghostly' presence that enables very intense laser light to be reflected or manipulated.

Dr Gregory Vieux, also from the University of Strathclyde, designed and undertook the experiments at the CLF with Professor Jaroszynski. He said:

“This new way of producing transient plasma mirrors could revolutionise accelerators and light sources, as it would make them very compact and capable of producing ultra-short duration ultra-intense pulses of light that are much shorter than can be produced easily by any other means.

Plasma can withstand intensities up to 1018 watts per square centimetre, which exceeds the threshold for damage of conventional optics by four or five orders of magnitude. This will allow the size of the optical elements to be reduced by two or three orders of magnitude, shrinking metre-sized optics to millimetres or centimetres."

This research is paving the way towards the development of the next generation of high-power lasers systems, ones that are more compact and more powerful.

Read the Nature Communications Physics publication to find out more about this research. 
Contact: Snelgrove, Kaylyn (STFC,RAL,CLF)