The next conference on laser filamentation COFIL 2026 will be organized in Palaiseau (France) in July 2026. COFIL 2026 is the 10th of a very successful series of biennial conferences bringing together scientists working in the field of ultrashort and intense laser filamentation and its applications. Registration is now open.
First images of the laser LLR laser firing up on the Saentis Mountain.
“Installé depuis le 18 mai au sommet du Säntis, dans les cantons d’Appenzell et St-Gall, un laser haute puissance vise à déclencher des éclairs et à guider la foudre loin des zones sensibles. Ce projet, intitulé «Laser Lightning Rod», est mené par un consortium européen dans lequel l’UNIGE a un rôle central. Des membres de la Section de physique de l’UNIGE ont participé au développement ainsi qu’au montage de la structure extérieure de l’expérience, dont certains éléments ont été installés par hélicoptère. Cet équipement est actuellement en phase de préparation pour pouvoir faire une campagne de mesures de juin à septembre, durant la haute saison des orages. Les chercheurs et chercheuses dirigeront le laser vers les orages et évalueront sa capacité à guider la foudre par le réchauffement et l’ionisation de l’air local.”
Many sensitive sites, such as nuclear power plants, power stations and other critical infrastructure may have insufficient lightning pro- tection and their electronic systems suffer damages due to direct or nearby lightning strikes. Similarly, thunderstorms paralyze airports every year, causing delays and requiring flights to be rerouted. A European consortium now plans to investigate and develop a new type of lightning protection using a high-power laser that will create ionized channels in the atmosphere and redirect lightning away from sensitive areas. The laser will be installed on the summit of the Säntis in the canton of Appenzell (Switzerland) and it will enter a test phase from June to September, during the peak thunderstorm season. On May 18, 2021, important elements of the experiment will be installed by helicopter. The École polytechnique (Paris, France), the University of Geneva (UNIGE, Switzerland), TRUMPF Scientific Lasers (Munich, Germany), André Mysyrowicz Consulting (AMC, France), the EPFL (Switzerland), the Haute école d’ingéniérie et de gestion du canton de Vaud – HEIG-VD (Switzerland) have joined forces to set up this European consortium.
T. Produit, T. Produit, P. Walch, C. Herkommer, A. Mostajabi, M. Moret, U. Andral, A. Sunjerga, M. Azadifar, Y.-B. André, B. Mahieu, W. Haas, B. Esmiller, G. Fournier, P. Krötz, T. Metzger, K. Michel, A. Mysyrowicz, M. Rubinstein, F. Rachidi, J. Kasparian, J.-P. Wolf, A. Houard, “The Laser Lightning Rod project,” The European Physical Journal, Applied Physics 92, 30501 (2020) http://dx.doi.org/10.1051/epjap/2020200243
Lightning is highly destructive due to its high power density and unpredictable character. Directing lightning away would allow to protect sensitive sites from its direct and indirect impacts (electromagnetic perturbations). Up to now, lasers have been unable to guide lightning efficiently since they were not offering simultaneously terawatt peak powers and kHz repetition rates. In the framework of the Laser Lightning Rod project, we develop a laser system for lightning control, with J-range pulses of 1 ps duration at 1 kHz. The project aims at investigating its propagation in the multiple filamentation regime and its ability to control high-voltage discharges. In particular, a field campaign at the Säntis mountain will assess the laser ability to trigger upward lightning.
(a) Principle of the general layout of the laser experiment implementation at Säntis (not to scale). (b) Schematic drawing of the sending telescope.
Installation of the laser for the Laser Lightning Rod Project (llr-fet.eu) in Orsay for the first experiments on the characterization of the filaments.
The laser delivers pulses of 700 mJ, 1 ps at 1 kHz (Photo @Pierre Walch, LOA)
The 700mJ / 900fs / 1kHz laser on his way to Orsay, France, for the first experiments in the frame of the Laser Lightning Rod Project https://llr-fet.eu/
@Clemens Herkommer, from Trumpf scientific lasers did a great job building the system.
C. Herkommer, P. Krötz, R. Jung, S. Klingebiel, C. Wandt, R. Bessing, P. Walch, T. Produit, K. Michel, D. Bauer, R. Kienberger, and T. Metzger, “Ultrafast thin-disk multipass amplifier with 720 mJ operating at kilohertz repetition rate for applications in atmospheric research,” Optics Express 28, 30164 (2020) https://doi.org/10.1364/OE.404185
We present an ultrafast thin-disk based multipass amplifier operating at a wavelength of 1030 nm, designed for atmospheric research in the framework of the Laser Lightning Rod project. The CPA system delivers a pulse energy of 720 mJ and a pulse duration of 920 fs at a repetition rate of 1 kHz. The 240 mJ seed pulses generated by a regenerative amplifier are amplified to the final energy in a multipass amplifier via four industrial thin-disk laser heads. The beam quality factor remains ∼ 2.1 at the output. First results on horizontal long-range filament generation are presented.
Picture of the first laser filaments produced with the LLR laser developed by Clemens Herkommer at Trumpf Scientific laser. (link)
