FEL2026 - 42nd International Free Electron Laser Conference

Evaluation of the synchronized operation between the infrared free-electron laser and fiber-laser by measuring the balanced cross-correlation via sum-frequency generation

THB01

27 Aug 2026, 11:30

20m

Contributed Oral Presentation Session 10: Electron Diagnostics, Timing, Synchronization, and Controls Electron Diagnostics, Timing, Synchronization, and Controls (Contributed)

Speaker

Keigo Kawase (National Institutes for Quantum Science and Technology)

Description

To demonstrate the stabilization of the carrier-to-envelope phase (CEP) of the free-electron laser oscillator via injection seeding, we are developing a fiber-laser-based, passively CEP-stabilized difference-frequency-generation mid-infrared source. The external injection seeding into the FEL requires a synchronized laser pulse with the electron bunch driving the FEL. Thus, we introduce a phase-locking system with the external radio-frequency signal into the fiber-laser system. To evaluate the performance of the synchronization, we performed a sum-frequency generation experiment using a fiber laser and an FEL at the infrared free-electron laser at the Institute of Advanced Energy, Kyoto University. The experimental technique used here is based on that previously demonstrated at the Fritz-Haber-Institut (R. Kiessling et al., Phys. Rev. Acc. and Beams 21, 080702 (2018)). In this report, we present our experimental results and discuss them. This research is carried out under the MEXT Q-LEAP program (contract number　JPMXS0118070271).