440 likes | 1.03k Views
Laser Cavity. M1 M2. 3D cavity. Fig.16-4. Photon Lifetime. Quality Factor and Cavity Finesse. Gaussian Beam. TEM 00 Mode. Amplitude of the Field. Phase Factors. Radius. TEM 0,0. TEM 1,0. TEM 2,0. Higher Order Modes. Fig.17-15.
E N D
3D cavity Fig.16-4
TEM0,0 TEM1,0 TEM2,0 Higher Order Modes
laser beam and field P n Fabry-perot (In-Plane)
A1 A2 A1 A2 A1’ A2’ a1 b2 T T T S B1 B2 B1 B2 B1’ B2’ b1 a2
A1 A2 a1 b2 T S B1 B2 b1 a2
a1 b2 b1 a2
n2 n1 n2 n1 DBR
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 = 2m
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
Broad-Area Etched-Facet Laser Cleaved Facet Etched Facet