Periodic Reporting for period 2 - THRILL (Technology for High-Repetition-rate Intense Laser Laboratories)
Reporting period: 2024-01-01 to 2025-06-30
The THRILL project provides new schemes and devices for pushing forward the limits of research infrastructures of European relevance and ESFRI landmarks in the field of high-energy high-repetition-rate lasers. Nine partners have joined forces not only to advance the technology but also to train a highly skilled workforce for tomorrow’s challenges in research infrastructures (RIs) and industry.
THRILL’s objectives outline a comprehensive strategy:
1. Overcome technical bottlenecks: THRILL focuses on developing the aspects of high-energy high-repetition-rate laser technology that up to now prevented to reach the technical readiness level required to specify and build the needed devices, through which sustainable and reliable operation of such laser beamlines can be guaranteed at the partnering RIs.
2. Address enabling technologies: Requiring the most urgent effort and timely attention by the community are (i) high-energy high-repetition-rate laser amplification, (ii) high-energy beam transport and (iii) optical coating resilience for large optics.
3. Produce several prototypes: The major activity within THRILL is organized around producing several prototypes demonstrating a high level of technical readiness.
4. Propose concrete steps: Through co-development between industry and academia, the advanced technologies up to prototyping in operational environments constitute the next steps to increase the performances and effectiveness of the industrial community.
5. Train a qualified work force: At last, the project is not only pushing technology, it is also offering an outstanding opportunity to train a highly needed qualified work force for RIs and industry.
With this in mind, the structure of THRILL promotes synergetic work, fast transfer to industry and integrated research activities at the European level.
THRILL’s objectives outline a comprehensive strategy:
1. Overcome technical bottlenecks: THRILL focuses on developing the aspects of high-energy high-repetition-rate laser technology that up to now prevented to reach the technical readiness level required to specify and build the needed devices, through which sustainable and reliable operation of such laser beamlines can be guaranteed at the partnering RIs.
2. Address enabling technologies: Requiring the most urgent effort and timely attention by the community are (i) high-energy high-repetition-rate laser amplification, (ii) high-energy beam transport and (iii) optical coating resilience for large optics.
3. Produce several prototypes: The major activity within THRILL is organized around producing several prototypes demonstrating a high level of technical readiness.
4. Propose concrete steps: Through co-development between industry and academia, the advanced technologies up to prototyping in operational environments constitute the next steps to increase the performances and effectiveness of the industrial community.
5. Train a qualified work force: At last, the project is not only pushing technology, it is also offering an outstanding opportunity to train a highly needed qualified work force for RIs and industry.
With this in mind, the structure of THRILL promotes synergetic work, fast transfer to industry and integrated research activities at the European level.
The technical and scientific work performed and the main achievements during the 30 months of the THRILL project are listed below for all technical work packages:
- Advanced Laser Architecture (WP3): We conducted a study within the end-user community and published a set of recommendation for the next generation of high-energy lasers at European RIs (Deliverable 3.1). As a complementary approach for reaching high-energy laser pulses at high repetition rate, we demonstrated for the first time the coherent combination of high-energy beams (Task 3.3) and published the results(DOI:10.1017/hpl.2024.84). We made significant progress in the development of an open-source holistic simulation environment for high-energy laser design and performance assessment: the OPOSSUM framework (https://www.thrill-project.eu/opossum/(opens in new window)). We also identified considerable interest from the community in such a simulation platform.
- High-Repetition-Rate Amplification (WP4): We performed a full characterization of the ELI ATON amplifier under thermal load and published our findings (Deliverable 4.1). We scaled up Amplitude's PAMDAM amplifier module to an aperture of 200 mm in diameter and characterized it. The results are available as part of Deliverable 4.2. We explored GSI's large aperture laser amplifier operation under thermal load and propose an improved design, the characterization of which is planned for 2026.
- Beam Transport and Beam Quality (WP5): We demonstrated real-time adaptive optics (RTAO) at the Apollon facility (DOI: 10.1017/hpl.2025.16). We designed and characterized a scaled-down version of an ajustable focusing system, which allows to vary the focus size of a large laser beam, without changing its location (Deliverable 5.3).
- Optics for High-Energy Lasers (WP6): We commissioned the thin-film coating chamber ELIAS at ELI for large optics and characterized first proof-of-principle coatings. We optimized anti-reflective coatings including a layer of Indium-Tin-Oxide (ITO) for the development of large-aperture Pockels cells. In oder to support the characterization of the produced coatings, we completed the commissioning of the laser-induced damage-threshold measurement station at ELI.
- Advanced Laser Architecture (WP3): We conducted a study within the end-user community and published a set of recommendation for the next generation of high-energy lasers at European RIs (Deliverable 3.1). As a complementary approach for reaching high-energy laser pulses at high repetition rate, we demonstrated for the first time the coherent combination of high-energy beams (Task 3.3) and published the results(DOI:10.1017/hpl.2024.84). We made significant progress in the development of an open-source holistic simulation environment for high-energy laser design and performance assessment: the OPOSSUM framework (https://www.thrill-project.eu/opossum/(opens in new window)). We also identified considerable interest from the community in such a simulation platform.
- High-Repetition-Rate Amplification (WP4): We performed a full characterization of the ELI ATON amplifier under thermal load and published our findings (Deliverable 4.1). We scaled up Amplitude's PAMDAM amplifier module to an aperture of 200 mm in diameter and characterized it. The results are available as part of Deliverable 4.2. We explored GSI's large aperture laser amplifier operation under thermal load and propose an improved design, the characterization of which is planned for 2026.
- Beam Transport and Beam Quality (WP5): We demonstrated real-time adaptive optics (RTAO) at the Apollon facility (DOI: 10.1017/hpl.2025.16). We designed and characterized a scaled-down version of an ajustable focusing system, which allows to vary the focus size of a large laser beam, without changing its location (Deliverable 5.3).
- Optics for High-Energy Lasers (WP6): We commissioned the thin-film coating chamber ELIAS at ELI for large optics and characterized first proof-of-principle coatings. We optimized anti-reflective coatings including a layer of Indium-Tin-Oxide (ITO) for the development of large-aperture Pockels cells. In oder to support the characterization of the produced coatings, we completed the commissioning of the laser-induced damage-threshold measurement station at ELI.
The results beyond state-of-the-art of the THRILL project are of scientific nature and the work is document in peer-reviewed publications:
- First demonstration of coherent beam combining with large-aperture laser beams - "Coherent combining of large-aperture high-energy Nd:glass laser amplifiers" DOI: 10.1017/hpl.2024.84
* Further work will be necessary to move from the proof-of-principle level to a full-scale demonstrator/prototype
- First demonstration of real-time adaptive optics (RTAO) at a high-power laser facility (Apollon) - "Apollon Real-Time Adaptive Optics (ARTAO) – Astronomy-Inspired Wavefront Stabilization in Ultraintense Lasers" DOI: 10.1017/hpl.2025.16
* Further work will be necessary to validate the concept at full size in routine operation conditions
- Identification of thermal load sources in large-aperture flash-lamp-pumped laser amplifiers - "The influence of flashlamp water cooling on long-term aberrations in large aperture Nd:glass amplifiers" DOI: 10.1117/12.3058409
* Our findings directly lead to the next version of the flashlamp cooling desing, implementing a number of improvements. Each iteration leads to an increase in technical readiness towards the realization in an operational environment.
- First demonstration of coherent beam combining with large-aperture laser beams - "Coherent combining of large-aperture high-energy Nd:glass laser amplifiers" DOI: 10.1017/hpl.2024.84
* Further work will be necessary to move from the proof-of-principle level to a full-scale demonstrator/prototype
- First demonstration of real-time adaptive optics (RTAO) at a high-power laser facility (Apollon) - "Apollon Real-Time Adaptive Optics (ARTAO) – Astronomy-Inspired Wavefront Stabilization in Ultraintense Lasers" DOI: 10.1017/hpl.2025.16
* Further work will be necessary to validate the concept at full size in routine operation conditions
- Identification of thermal load sources in large-aperture flash-lamp-pumped laser amplifiers - "The influence of flashlamp water cooling on long-term aberrations in large aperture Nd:glass amplifiers" DOI: 10.1117/12.3058409
* Our findings directly lead to the next version of the flashlamp cooling desing, implementing a number of improvements. Each iteration leads to an increase in technical readiness towards the realization in an operational environment.