Laser Cavity

1. Laser Cavity

2. M1 M2

3. 3D cavity Fig.16-4

4. Photon Lifetime

5. Quality Factor and Cavity Finesse

6. Gaussian Beam

7. TEM00Mode

8. Amplitude of the Field

9. Phase Factors

10. Radius

12. TEM0,0 TEM1,0 TEM2,0 Higher Order Modes

13. Fig.17-15

14. Gain Profile and Longitudinal Modes

15. Spectrum

16. laser beam and field P n Fabry-perot (In-Plane)

17. A1 A2 A1 A2 A1’ A2’ a1 b2 T T T S B1 B2 B1 B2 B1’ B2’ b1 a2

18. A1 A2 a1 b2 T S B1 B2 b1 a2

19. a1 b2 b1 a2

20. Building Block Components

21. Fabry Perot Etalon

24. Fabry Perot Laser

25. n2 n1 n2 n1 DBR

30. Comparison of DQEs of Cleaved and Etched facet EE Lasers Facet Cleaved & Cavity length 350 m One Facet Etched & Cavity length 380 m Mesa width 4 m Mesa width 3 m Mesa width 2 m Mesa Width 22 m DQE = 0.38 for w = 22 m DQE = 0.38 for w = 3 m DQE = 0.31 for w = 4 m DQE = 0.26 for w = 2m

31. Mesa width 22 m 100 L340 L370 90 L400 80 One facet etched the other cleaved Double Cleaving 70 60 Output Power (mW) 50 40 30 20 10 0 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 2 Current Density (A/cm ) Comparison of DQEs of Cleaved and Etched facet EE Lasers (Broad area) DQE = 0.4 for double-cleaved DQE = 0.33 for etched facet

32. Broad-Area Etched-Facet Laser Cleaved Facet Etched Facet