Dear Colleagues,

The development of chirped pulse amplification for ultrashort laser pulses made possible the production of extreme light intensities and subsequently enabled the investigation of a plethora of new processes.

The scientific community is now facing a transition phase, from laboratory to facility-grade laser-driven sources. This requires the harmonization of the metrology for laser-driven primary and secondary sources across the facilities, as a central request of the lasers scientific community and of the non-specialist beamtime beneficiaries at these facilities.

Several commercial spectral, spatial, temporal or energy metrology techniques are de facto standards in the metrology of these laser-driven sources. However, as these sources evolve, the knowledge boundary shifts towards more advanced, sophisticated, innovative, and specialized methods, to be discussed in the articles of this issue. Furthermore, the interplay and limitations of the existing metrology devices and beam sampling techniques may also be addressed.

The laser-driven sources cover the entire spectral range, from the electromagnetic pulses in the radiofrequency region and THz radiation to x-rays and gamma rays. However, a significant part of the metrology of extreme light-driven radiation sources includes electron, ion, and further particle radiation. The latest sources are also closely related to the qualification of their respective driving laser sources and can be considered as part of the proposed topic of this Photonics Special Issue.

We are inviting the scientific community to contribute research articles and review papers engaging in laser and laser-driven sources metrology. Research areas may include (but are not limited to) metrology subjects related to primary and secondary sources at laser facilities:

• pulse sampling
• review of metrology procedures and technologies
• new instrumentation for metrology
• indirect characterization of extreme light-driven sources through experiments

We look forward to receiving your contributions.

Dr. Daniel Ursescu
Dr. Zsolt Divéki
Dr. Uddhab Chaulagain
Dr. Gabriele Maria Grittani
Dr. Michael Ehret
Guest Editors

Manuscript Submission Information

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• extreme light facilities
• ultra-intense laser pulses
• ultrafast metrology
• laser-driven radiation sources (electron, ion and proton, etc.) metrology
• diagnostic devices, procedures, and protocols for metrology
• electromagnetic, terahertz, infrared, visible, ultraviolet, X-ray and gamma radiation metrology