1. Laser stability Takuya Natsui

2. Oscillator phase lock stability

3. Cavity length driftPhase lock stabilityPrice Menlo products<< 0.1 um0.0 (detection limit) $ 150000 (1800 万円 ) Oscillator 13 um2.0 deg $ 35000 (400 万円 ) Oscillator 21 um0.58 deg $ 35000 (400 万円 ) Oscillator3 ANDi type 1 um0.64 deg $ 35000 (400 万円 )

4. Stability ： 0.58 deg Stability ： 0.64 deg Stability ： 2.0 deg Piezo position (cavity length drift)

5. Oscillator phase lock system

6. Zurich Instruments UHFIL Lok-in Amplifier Stability: 1.5 deg in 2856 MHz 0.3 deg in 571 MHz 0.056 deg in 114 MHz Commercial products also tested

7. Developed synchronization system Commercial products Stability: 1.5 deg Stability: 0.64 deg Compared in same oscillator, developed synchronization system has enough capability. $10000 $60000

8. laser operation log

9. Laser system and detect point Yb-doped fiber oscillator with Transmission grating Yb-doped fiber pre amplifier Yb-doped fiber main amplifier Pulse picker Yb:YAG thin-disk multi- pass cavity amplifier Yb:YAG thin-disk multipass amplifier ×3 SHG Synchronization system SHG RF GUN 51.9 MHz 2, 5, 25, 50 Hz Single or Double bunch 0.2 nJ @ 1037 nm Yb-doped fiber main amplifier Transmission grating pair stretcher 2856 MHz trigger From Accelerator Yb-doped fiber pre amplifier >μJ @ 1037 nm Pulse picker 10 MHz Fix the configuration to 25 Hz operation PD2 PD1 PD3 PD4 Power meter We have five constant monitoring points. Photo diode x4, Power meter x1

10. Detector (photo diode) Laser pulse power is detected with photo diodes and oscilloscope.

11. start-up First, fiber amplifier drifts Fiber amp. Disk amp.1 Disk amp.2 Disk amp.3 Laser is stabled gradually

12. Sometimes fiber amplifier drifts Disk amplifier is damaged

13. Recently, 1 or 2 days stabilization was achieved.

14. Fix Disk amplifier is damaged BPM error Recent operation log We achieved two days stable operation. (0.7 +/-0.3 nC) BBO Fundamental laser power Beam charge

15. Still long term drift occur. We will increase detection points. Develop power feed back systems. Pointing stability detector is also developing with quadrant sensor.

18. Oscillator phase detect 52 or 114 MHz IQ signal 2856 MHz IQ signal