| Report number | CERN-PBC-Notes-2024-005 |
| Title | 710 kW stable average-power in a 45,000 finesse two-mirror optical cavity |
| Author(s) | Lu, Xin-Yi (Tsinghua University) ; Martens, Aurelien (Université Paris-Saclay (FR)) |
| Publication | 2024 |
| Imprint | 2024-11-13 |
| Number of pages | 4 |
| Subject category | Accelerators and Storage Rings |
| Study | Physics Beyond Colliders |
| Project | Gamma Factory |
| Abstract | Very-high average optical enhancement cavities are be- ing used both in fundamental and applied research. The most demanding applications require stable megawatt level average power of infrared picosecond pulses with repetition rates of several tens of MHz. Towards reach- ing this goal, we report on the achievement of 710 kW of stable average power in a two-mirror hemispherical op- tical enhancement cavity. This result further improves on the state of the art. We observed the influence of thermal lensing induced by residual absorption in the coating. This is observed for the first time in this context, though the effect was well predicted in literature. Exper- imental observations are matched with a simple model of thermal effects in the mirror’s coatings. These results set a further stage to design an optimized optical system for several applications where very high average-power enhancement cavities are expected to be operated. |
| Submitted by | aurelien.martens@cern.ch |
Record created 2024-11-13, last modified 2024-11-13