Laser oscillator synchronization with RF reference signal is ultra-important for a modern light source based on the accelerator.For Tsinghua Thomson scattering X-ray source,we have synchronized the mode-locked laser o...Laser oscillator synchronization with RF reference signal is ultra-important for a modern light source based on the accelerator.For Tsinghua Thomson scattering X-ray source,we have synchronized the mode-locked laser oscillator to RF reference signal with 48.2 fs RMS relative jitter.Both fundamental and harmonic signals derived from photo diode detection are used for laser-RF synchronization in our scheme.The fundamental signal is for coarse laser-RF synchronization and multiple laser oscillator synchronization.The harmonic signal is for high precise phase locking.The digital phase detector is implemented in the synchronization scheme for less noise,replacing the mixing to DC phase detection scheme.The digital processing algorithm for synchronization is commonly used in low-level RF control field.In order to test the phase locking loop logic without damaging the real laser oscillator,a laser oscillator emulator was developed for phase locking.This paper will report the laser-RF synchronization scheme and its performance.The laser oscillator emulator system will also be introduced here.展开更多
Optical enhancement cavity(OEC)is a powerful tool for fundamental research and diagnostics.In this paper,the progress of a continuous-wave OEC to realize of megawatt cavity for a novel light source based on a steady-s...Optical enhancement cavity(OEC)is a powerful tool for fundamental research and diagnostics.In this paper,the progress of a continuous-wave OEC to realize of megawatt cavity for a novel light source based on a steady-state microbunching(SSMB)mechanism,is reported.After efficiently suppressing all external noise and optimizing the alignment,mode-matching,and polarization matching,stable and long-term locking is achieved with the help of two feedback loops.The modal instability phenomenon caused by the surface thermoelastic deformation is observed.A pair of D-shape mirrors are utilized to remove the high-order modes.Finally,an intra-cavity average power of 30 kW is reached.展开更多
文摘Laser oscillator synchronization with RF reference signal is ultra-important for a modern light source based on the accelerator.For Tsinghua Thomson scattering X-ray source,we have synchronized the mode-locked laser oscillator to RF reference signal with 48.2 fs RMS relative jitter.Both fundamental and harmonic signals derived from photo diode detection are used for laser-RF synchronization in our scheme.The fundamental signal is for coarse laser-RF synchronization and multiple laser oscillator synchronization.The harmonic signal is for high precise phase locking.The digital phase detector is implemented in the synchronization scheme for less noise,replacing the mixing to DC phase detection scheme.The digital processing algorithm for synchronization is commonly used in low-level RF control field.In order to test the phase locking loop logic without damaging the real laser oscillator,a laser oscillator emulator was developed for phase locking.This paper will report the laser-RF synchronization scheme and its performance.The laser oscillator emulator system will also be introduced here.
基金the Fund from Tsinghua University Initiative Scientific Research Program,China(Grant No.20191081195).
文摘Optical enhancement cavity(OEC)is a powerful tool for fundamental research and diagnostics.In this paper,the progress of a continuous-wave OEC to realize of megawatt cavity for a novel light source based on a steady-state microbunching(SSMB)mechanism,is reported.After efficiently suppressing all external noise and optimizing the alignment,mode-matching,and polarization matching,stable and long-term locking is achieved with the help of two feedback loops.The modal instability phenomenon caused by the surface thermoelastic deformation is observed.A pair of D-shape mirrors are utilized to remove the high-order modes.Finally,an intra-cavity average power of 30 kW is reached.
