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0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18 0.20 0.220

10

20

30

40

50

60

70

Out

put P

ower

(mW

)

Current (A)

Facet Cleaved&

Cavity length 350 m

Mesa width 3 m

Mesa Width 22 m

0.00 0.02 0.04 0.06 0.08 0.10 0.120

5

10

15

20

25

30

35

Out

put P

ower

(mW

)

Current (A)

L380W2 L380W4

One Facet Etched&

Cavity length 380 m

Comparison of DQEs of Cleaved and Etched facet EE Lasers

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

Mesa width 4 m

Mesa width 2 m

Comparison of DQEs of Cleaved and Etched facet EE Lasers

(Broad area)

DQE = 0.4 for double-cleaved

DQE = 0.33 for etched facet

One facet etched the

other cleavedDouble Cleaving

Mesa width 22 m

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 55000

10

20

30

40

50

60

70

80

90

100

Ou

tpu

t P

ow

er

(mW

)

Current Density (A/cm2)

L340 L370 L400

Etched Facet

Cleaved Facet

Broad-Area Etched-Facet Laser