23.4 Lasers
687
(a)
InP substrate
InAlGaAs n-DBR
QW active region
laser
drive
contact
tuning contact
AlGaAs p-DBR
laser output
AlGaAs n-DBR
(b)
(c)
1550 1550 1554 1558 1562 1566 1570
0
-20
-40
-60
Intensity (arb. units)
Wavelength (nm)
SMSR>45 dB
20 channels @ 100 GHz
Fig. 23.71 a Schematic setup and b SEM image of VCSEL with air gap between active layer and top Bragg mirror, c
spectra for different tuning conditions (via the width of the air gap). From [2026]
Fig. 23.72 a VCSEL with air gap and b Bragg mirror with high dielectric contrast InP/air interfaces. Reprinted with
permission from [2027], ©2002 IEEE
(a)
hemispheric
focusing
optics
semiconductor
intra-cavity
resonator
(b)
Fig. 23.73 a Schematic setup of optically pumped semiconductor laser (OPSL). The semiconductor chip consists of a
Bragg mirror on the bottom, multiple quantum wells and an antireflection coating on the top. Adapted from [2028]. b
OPSL source (488 nm, 20 mW, footprint: 125 × 70 mm 2 ). Reprinted with permission from [2029]
687
(a)
InP substrate
InAlGaAs n-DBR
QW active region
laser
drive
contact
tuning contact
AlGaAs p-DBR
laser output
AlGaAs n-DBR
(b)
(c)
1550 1550 1554 1558 1562 1566 1570
0
-20
-40
-60
Intensity (arb. units)
Wavelength (nm)
SMSR>45 dB
20 channels @ 100 GHz
Fig. 23.71 a Schematic setup and b SEM image of VCSEL with air gap between active layer and top Bragg mirror, c
spectra for different tuning conditions (via the width of the air gap). From [2026]
Fig. 23.72 a VCSEL with air gap and b Bragg mirror with high dielectric contrast InP/air interfaces. Reprinted with
permission from [2027], ©2002 IEEE
(a)
hemispheric
focusing
optics
semiconductor
intra-cavity
resonator
(b)
Fig. 23.73 a Schematic setup of optically pumped semiconductor laser (OPSL). The semiconductor chip consists of a
Bragg mirror on the bottom, multiple quantum wells and an antireflection coating on the top. Adapted from [2028]. b
OPSL source (488 nm, 20 mW, footprint: 125 × 70 mm 2 ). Reprinted with permission from [2029]