The document discusses microresonator-based optical frequency combs, focusing on the generation of pulse trains using passively mode-locked lasers. Key elements include the role of the gain medium and saturable absorber mirror in pulse generation, as well as the effects of dispersion on frequency comb generation. It highlights experimental results and various applications of these technologies.

1. Microresonator-Based Optical
Frequency Combs
Presenter: Hossein Babashah

2. Generation of a pulse train in a passively mode-locked laser. The gain medium compensates for
losses, and the saturable absorber mirror (SA) enforces pulse generation. Each time the
circulating pulse hits the output coupler mirror (OC), a pulse is emitted in the output.
Mode Lock LASER

3. 𝑓𝑛 ∼ 1𝑇𝐻𝑧
Frequency Comb Generation (Mode Lock LASER
SPECTRUM)

4. Continuous Wave Laser (CW LASER)
Facile Gain Requirement!
Microwatt nonlinearity

5. Frequency Comb Generation by CW LASER
Concept
Microwatt input, W output

7. Whispering gallery mode Resonator
low loss (WGMR)

8. Frequency Comb Generation by a LASER
Concept

9. Four Wave Mixing

10. Dispersion as a Limiting factor
Dispersion=>non-degenerate =>anti-symmetry=>Bandwidth (not identical distance for fr)
Dipsersion
1.normal (shorten distance as frequency increase)
2.anomalous (longer distance as frequency increase) (this case)

11. Experimental Result

12. Optical frequency comb technologies as a function of their mode spacing
and fractional bandwidth

13. Applications

14. Applications

15. Applications

16. Applications

17. Applications

18. Conclusion
• Watt Microwatt nonlinearity Frequency Comb
• Wide Applications
• Dispersion limitation

19. Reference
• [1] Kippenberg, Tobias J., Ronald Holzwarth, and S. A. Diddams.
"Microresonator-based optical frequency combs." Science 332, no.
6029 (2011): 555-559.
• [2] Wikipedia