1. Fiber Laser for ERL Zach Ulibarri Mentor: Zhi Zhao

2. Introduction Goal: – Mode locked laser oscillator – 50 MHz repetition rate – Designed for emittance measurement

3. Laser Basics Population inversion in gain medium

4. Laser Basics Stimulated photon emission

5. Laser Basics Light emits and repeats process

6. Mode Locked Lasers Saturable absorber Intensity Transmission

7. Mode Locked Lasers With saturable absorber in place, random noise can create pulses

8. Mode Locked Lasers How do we add sufficient noise to the cavity?

9. Mode Locked Lasers How do we add sufficient noise to the cavity?

10. Artificial Saturable Absorber Wave plates create phase shift induced intensity modulation

11. Experimental Setup

12. Top View

13. Mode Locked Lasers 19.8ns

14. Mode Locked Lasers Detector is too slow FWHM suggests Pulse width = 1.22 ns

15. Autocorrelator Measurement Michelson interferometer creates small delay Aligned pulses create second harmonic generation

16. Intensity Autocorrelation

17. FWHM suggests pulse width = 8ps. Very large!

18. Chirp Index of refraction depends on wavelength Compensate with diffraction grating

19. Chirp

20. Intensity Autocorrelation

21. Dechirped Autocorrelation

22. FWHM = 330 fs = 1.5*220

23. Interferometric Autocorrelation FWHM suggests pulse width = 220fs

24. Spectrum

25. Simulated Results 200fs Agrees with estimates

26. Pulse Energy

27. Peak Power ChirpedDechirped

28. Questions?