Pevnolátkové lasery - eLearn...
Transcript of Pevnolátkové lasery - eLearn...
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PevnolPevnoláátkovtkovéé laserylasery
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PevnolPevnoláátkovtkovéé laserylasery
AktAktíívne lvne láátkytky pevnolátkových (dielektrických) laserov pozostávajú z maticovej látky a aktívnej prímesi.
- maticová látka- monokryštalická (Al2O3, CaWO4,YAG ...)- amorfná (sklo)
- aktívná prímes- vzácne zeminy (Nd, Er, Pr, Ho ... ) - prvky zo skupiny železa (Cr, Ti, ...)
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PevnolPevnoláátkovtkovéé laserylasery
Čerpanie pevnolátkových laserov
Pevnolátkové lasery sú typicky čerpané opticky a to:
1. Nekoherentným zdrojom – výbojkou (Hg, Xe, ...)
2. Koherentným zdrojom – laserovými diódami (DPSS)
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PevnolPevnoláátkovtkovéé laserylasery
Najvýznamnejšie pevnolátkové lasery:
1. Rubínový laser (prvý laser)
2. Nd:YAG (Neodýmový) laser
3. Vláknové lasery
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PevnolPevnoláátkovtkovéé laserylasery
Spôsoby optického čerpania pevnolátkových laserov pomocou výbojok
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RubRubíínový lasernový laser
Energetický diagram rubínového lasera
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RubRubíínový lasernový laser
Konštrukcia prvého rubínového lasera
(Theodore Maiman, 1960)
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Princíp: Trojúrovňový systém
Vlnová dĺžka: λ = 694 nm VIS - červená
Maticová látka: zafír - Al2O3
Aktívny prvok: chróm Cr3+ , koncentrácia cca. 0,05 %
Rozmery: priemer φ = 5 ÷ 15 mm, dĺžka l = 50 ÷ 250 mm
Účinnosť: η ~ 0,05 ÷ 0,1 %
Čerpanie: Výbojky – Xe, Hg
Režim činnosti: Impulzný, fop ≈ 0,1 – 0,01 Hz
Výstupná energia : Q ~ 0,1 ÷ 10 J
Aplikácie: Impulzná holografia, Lidar, medicína
RubRubíínový lasernový laser
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NdNd YAG laserYAG laser
Energetický diagram Nd:YAG lasera
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NdNd YAG laserYAG laserPrincíp činnosti: štvorúrovňový systém
Vlnová dĺžka: λ = 1064 nm IR, druhá harmonická 532 nm
Maticová látka: Ytrium hlinitý granát – Y3Al5O12 (YAG)
Aktívna prímes: Neodym Nd3+ , 1 ÷ 6 %
Rozmery: priemer φ = 5 ÷ 15 mm, dĺžka l = 80 ÷ 150 mm
Účinnosť: η ~ 2 ÷ 5 %
Režim činnosti: Spojitý, impulzný, modulácia kvality
Čerpanie: výbojky – Xe, laserové diódy – DPSS (η až 25 %)
Výstupný výkon: Pout ~ 1 ÷ 3000 W
Aplikácie: Technológie, medicína, metrológia, spektroskopia
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NdNd YAG laserYAG laserKonštrukcia
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DPSS Nd:YAGDPSS Nd:YAG laserylaseryU tohto typu konštrukcie laserov sú čerpacie výbojky nahradené
výkonovými laserovými diódami alebo diódovými poliami.
ZrkadloZrkadlo ZrkadloZrkadlo
ChladiacakvapalinaChladiacakvapalina
Čerpaciaoptika
Čerpaciaoptika
KryštálKryštál
Laserovádióda
Laserovádióda
Konštrukcia čelne a bočne čerpaných DPSS laserov.
ChladiacakvapalinaChladiacakvapalina
Čerpaciaoptika
Čerpaciaoptika
Laserovépolia
Laserovépolia
KryštálKryštál
ZrkadloZrkadlo
ZrkadloZrkadlo
ChladiacakvapalinaChladiacakvapalina
KryštálKryštál
Čerpaciaoptika
Čerpaciaoptika
Optický lúčlasera
Optický lúčlasera
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DPSS Nd:YAG laseryDPSS Nd:YAG lasery
VÝHODY DIÓDOVO ČERPANÝCH LASEROV V SKRATKE (1)
Spoľahlivosť a životnosť: Výbojky sa vypália nepredvídateľne a často. Výmena výbojok sa spravidla doporučuje po 500 – 1000 hodináchprevádzky. Životnosť diódových polí je viac ako 20 000 hodín.
Väčšia účinnosť: Diódové polia majú väčšiu elektrickú účinnosť akovýbojky. Žiarenie diódových polí pre Nd:YAG lasery je optimalizované navlnovú dĺžku 808 nm ± 3 nm, ktorá je v YAG veľmi dobre absorbovaná, zatiaľ čo 95% žiarenia z výbojok sa premení na stratové teplo.Celková účinnosť je 15 - 20% (bežné Nd:YAG lasery 2 – 5%).
Nižšie napäťové požiadavky: Diódami čerpané lasery nevyžadujú takévysoké napätie ako ekvivalentné lasery čerpané výbojkami. Požadovanýpríkon diódovo čerpaných laserov je typicky 5-10% príkonu ekvivalentnýchvýbojkou čerpaných laserov. Nepotrebujú trojfázový el. rozvod
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DPSS Nd:YAG laseryDPSS Nd:YAG lasery
VÝHODY DIÓDOVO ČERPANÝCH LASEROV V SKRATKE (2)
Kompaktný dizajn: Konštrukcia diódovo čerpaných laserov je menšia a viackompaktnejšia a užívateľsky príjemnejšia.
Kvalita zväzku: Diódovo čerpané lasery sú dobre známe výbornýmivlastnosťami výstupného zväzku. Toto platí najmä pre čelne čerpané lasery, kde M2 pri plnom výkone je ~20 pre väčšinu systémov zatiaľ čo pre výbojkami čerpané lasery je spravidla >40.
Menšie tepelné straty: Chladenie diódovo čerpaných laserov jezabezpečené uzavretým okruhom so štandardnou destilovanou vodou, bezpotreby použitia deionizovanej vody ako v prípade laserov čerpanýchvýbojkami.
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DPSS Nd:YAG laseryDPSS Nd:YAG lasery
Porovnanie spektier absorpcie Nd:YAG kryštálu s emisnými spektrami výbojkya laserovej diódy vyžarujúcej na 808 nm
λ = 808 nm
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VlVlááknovknovéé laserylasery
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VlVlááknovknovéé laserylasery
Principiálna schéma konštrukcie výkonového vláknového lasera
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EDFA: PEDFA: Principrincip ččinnostiinnosti
1480 nmČerpanie
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Output vs wavelength
Amplification between 1.53 and 1.56 um.
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VlVlááknovknovéé laserylasery
Súčasné možnosti realizácie vláknových laserov
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POLOVODIPOLOVODIČČOVOVÉÉ LASERYLASERY
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PolovodiPolovodiččovovéé laserylasery
Polovodiče – energetické diagramy
E
CB
k–k
Direct Bandgap
(a) GaAs
E
CB
VB
Indirect Bandgap, Eg
k–k
kcb
(b) Si
E
k–k
Phonon
(c) Si with a recombination center
Eg
Ec
Ev
Ec
Ev
kvb VB
CB
ErEc
Ev
Photon
VB
(a) In GaAs the minimum of the CB is directly above the maximum of the VB. GaAs istherefore a direct bandgap semiconductor. (b) In Si, the minimum of the CB is displaced fromthe maximum of the VB and Si is an indirect bandgap semiconductor. (c) Recombination ofan electron and a hole in Si involves a recombination center .
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
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PolovodiPolovodiččovovéé laserylasery
Ek
kš /a–š /a
Ec
Ev
ConductionBand (CB)
Ec
Ev
CB
The E-k Diagram The Energy BandDiagram
Empty ψk
Occupied ψkh+
e-
Eg
e-
h+
hυ
VB
hυ
ValenceBand (VB)
The E-k diagram of a direct bandgap semiconductor such as GaAs. The E-kcurve consists of many discrete points with each point corresponding to apossible state, wavefunction ψk(x), that is allowed to exist in the crystal.The points are so close that we normally draw the E-k relationship as acontinuous curve. In the energy range Ev to Ec there are no points (ψk(x)solutions). © 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
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PolovodiPolovodiččovovéé laserylasery
E1
E2
hυ
(a) Absorption
hυ
(b) Spontaneous emission
hυ
(c) Stimulated emission
In hυOut
hυ
E2 E2
E1 E1
Absorption, spontaneous (random photon) emission and stimulatedemission.© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
Optické prechody v polovodičoch
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PolovodiPolovodiččovovéé laserylasery
P+ δP
Laser medium
x
δ x
P
(a) A laser medium with an optical gain (b) The optical gain curve of the medium. Thedashed line is the approximate derivation in the text.
h υE 2
E 1
υ
Optical Gain
υ ο
∆ υ
(a) (b)
g ( υ )
g ( υ o )
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
Zosilnenie optického žiarenia v polovodiči
)h(B)NN( )h(BN)h(BN
emission photon stimulated of rateNet dt
dN
2112
211212
ph
υρ−=υρ−υρ=
=Pre zosilnenie treba:
N2 > N1
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PolovodiPolovodiččovovéé laserylasery
Podmienka získania inverznej populácie:EFn – EFp > Eg
hυEg
Optical gain EFn − EFp
Optical absorption
0
Energy
Ec
Ev
CB
VB
(a) The density of states and energy distribution of electrons and holes inthe conduction and valence bands respectively at T ≈ 0 in the SCLunder forward bias such that EFn − EFp > Eg. Holes in the VB are emptystates. (b) Gain vs. photon energy.
Density of states
Electronsin CB
Holes in VB= Empty states
EFn
EFp
eV
At T > 0
At T = 0
(a) (b)
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
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PolovodiPolovodiččovovéé laserylasery
(a) Optical gain vs. wavelength characteristics (called the optical gain curve) of thelasing medium. (b) Allowed modes and their wavelengths due to stationary EM waveswithin the optical cavity. (c) The output spectrum (relative intensity vs. wavelength) isdetermined by satisfying (a) and (b) simultaneously, assuming no cavity losses.
(c)
Relative intensity
δλm
Optical Gain
λ
Allowed Oscillations (Cavity Modes)
δλm
(b)
L
Stationary EM oscillationsMirrorMirror
λλ
Dopplerbroadening
m(λ/2) = L
(a)
λο
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
Aktívna látka –
polovodič
Rezonátor
Výstupnéžiarenie
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PolovodiPolovodiččovovéé laserylasery
L
PiPf
R1R2
Steady state EM oscillations
Optical cavity resonator
Reflectingsurface
Reflectingsurface
Cavity axis x12
Ef Ei
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
1/ == ifop PPG
)]2(exp[)]2(exp[21 LLgRRPP if γ−Γ=
⎟⎠⎞
⎜⎝⎛+=Γ
21
1ln21.
RRLgth γ
309.05.315.31 22
21
21 =⎟⎠⎞
⎜⎝⎛
+−
=⎟⎠⎞
⎜⎝⎛
+−
=nnnnR
Γ – koeficient optického prispôsobenia
Prahový zisk Prahový zisk –– prahový prahový ččerpacerpacíí prprúúdd
thth th
BIg BJArea
= =B – konštrukčný parameter
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PolovodiPolovodiččovovéé laserylasery
02112 )(
υυ
nhBcgNN thth∆
≈−
Simplified description of a laser oscillator. ( N2 − N1) andcoherent output power ( Po) vs. pump rate under continuouswave steady state operation.
Pump rate
Threshold pump rate
(N2 − N1)th
N2 − N1
Threshold populationinversion
Po = Lasing output power(N2 − N1) and Po
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
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PolovodiPolovodiččovovéé laserylasery
p+ n+
EF n
(a)
Eg
Ev
Ec
Ev
Holes in V BElectrons in C B
Junction
Electrons Ec
p+
Eg
V
n+
(b)
EF n
eV
EF p
The energy band diagram of a degenerately doped p-n with no bias. (b) Banddiagram with a sufficiently large forward bias to cause population inversion andhence stimulated emission.
Invers ionreg ion
EF p
EcEc
eVo
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
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PolovodiPolovodiččovovéé laserylasery
0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6λ
1.7Infrared
GaAs1-yPy
In1-xGaxAs1-yPyAlxGa1-xAs
x = 0.43
Indirectbandgap
Free space wavelength coverage by different LED materials from the visible spectrum to theinfrared including wavelengths used in optical communications. Hatched region and dashedlines are indirect E materials
In0.49AlxGa0.51-xP
PolovodiPolovodičče pre výrobu LAD vo VIS a NIR e pre výrobu LAD vo VIS a NIR ččasti spektraasti spektra
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PolovodiPolovodiččovovéé laserylasery
0.20.4
0.60.8
11.21.4
1.61.8
22.2
2.42.6
0.54 0.55 0.56 0.57 0.58 0.59 0.6 0.61 0.62Lattice constant, a (nm)
GaP
GaAs
InAs
InP
Direct bandgapIndirect bandgap
In 0.535 Ga 0.465 AsX
Quaternary alloyswith direct bandgap
In 1- xGa xAs
Quaternary alloyswith indirect bandgap
Eg (eV)
Ba ndga p ene rgy Eg a nd la ttic e cons tant a for va rious III-V a lloys ofG a P, G aA s , InP a nd InA s. A line repre se nts a te rna ry a lloy form e d w ithc om pounds from the end points of the line . Solid line s a re for dire c tbandga p a lloys w he rea s da she d line s for indirec t ba ndga p a lloys .Re gions be tw e en line s re pre se nt qua te rna ry a lloys . The line from X toInP repre se nts qua te rna ry a lloys In1-xG a xA s 1-yPy m a de fromIn0.535 G a 0.465 A s a nd InP w hich a re la ttic e m a tched to InP.© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
PolovodiPolovodičče pre výrobu LAD e pre výrobu LAD –– InGaAsP/InPInGaAsP/InP
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PolovodiPolovodiččovovéé laserylasery
Laserová dióda s jednoduchým heteroprechodom
hυ - Eg
Eg (b)
V
(a)
p n+
Eg
eVo
EF
p n+
Electron in CBHole in VB
Ec
Ev
Ec
Ev
EF
eVo
Electron energy
Distance into device
(a) The energy band diagram of a p-n+ (heavily n-type doped) junction without any bias.Built-in potential Vo prevents electrons from diffusing from n+ to p side. (b) The appliedbias reduces Vo and thereby allows electrons to diffuse, be injected, into the p-side.Recombination around the junction and within the diffusion length of the electrons in thep-side leads to photon emission.
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
Laserová dióda s dvojitým heteroprechodom
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PolovodiPolovodiččovovéé laserylasery
Refractiveindex
Photondensity
Activeregion
∆n ~ 5%
2 eV
Holes in VB
Electrons in CB
AlGaAsAlGaAs
1.4 eV
Ec
Ev
Ec
Ev
(a)
(b)
pn p
∆Ec
(a) A doubleheterostructure diode hastwo junctions which arebetween two differentbandgap semiconductors(GaAs and AlGaAs).
2 eV
(b) Simplified energyband diagram under alarge forward bias.Lasing recombinationtakes place in the p-GaAs layer, theactive layer
(~0.1 µm)
(c) Higher bandgapmaterials have alower refractiveindex
(d) AlGaAs layersprovide lateral opticalconfinement.
(c)
(d)
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
GaAs
Laserová dióda s dvojitým heteroprechodom, DC PBH – index guided
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PolovodiPolovodiččovovéé laserylasery
L Electrode
Current
GaAs
GaAsn+
p+
Cleaved surface mirror
Electrode
Active region(stimulated emission region)
A schematic illustration of a GaAs homojunction laserdiode. The cleaved surfaces act as reflecting mirrors.
L
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
Ipr = gth . A
A – plocha aktívnej oblasti
gth – prahováprúdová hustota
Veľkoplošná laserová dióda
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PolovodiPolovodiččovovéé laserylasery
Roztekanie prRoztekanie prúúdduu mmomo aktomo aktíívnej oblasti LAD vnej oblasti LAD –– leakage currentleakage current
Schematic illustration of the the structure of a double heterojunction stripecontact laser diode
Oxide insulator
Stripe electrode
SubstrateElectrode
Active region where J > Jth.(Emission region)
p-GaAs (Contacting layer)
n-GaAs (Substrate)
p-GaAs (Active layer)
Currentpaths
L
W
Cleaved reflecting surfaceEllipticallaserbeam
p-AlxGa1-xAs (Confining layer)
n-AlxGa1-xAs (Confining layer) 12 3
Cleaved reflecting surface
Substrate
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
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PolovodiPolovodiččovovéé laserylasery
MetMetóódy lokalizdy lokalizáácie prcie prúúdduu do aktdo aktíívnej oblasti LADvnej oblasti LAD
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PolovodiPolovodiččovovéé laserylasery
Dvojitým rastom planDvojitým rastom planáárne vymedzenrne vymedzenéé heteroheterošštrutrukkttúúry ry –– index guided, DC PBHindex guided, DC PBH
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PolovodiPolovodiččovovéé laserylasery
Schematic illustration of the the structure of a double heterojunction stripecontact laser diode
Oxide insulator
Stripe electrode
SubstrateElectrode
Active region where J > Jth.(Emission region)
p-GaAs (Contacting layer)
n-GaAs (Substrate)
p-GaAs (Active layer)
Currentpaths
L
W
Cleaved reflecting surfaceEllipticallaserbeam
p-AlxGa1-xAs (Confining layer)
n-AlxGa1-xAs (Confining layer) 12 3
Cleaved reflecting surface
Substrate
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
Ziskom vymedzenZiskom vymedzenáášštrukttruktúúrara
(Gain Guided)
Typická štruktúra hranovo emitujúcej laserovej diódy s DH
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PolovodiPolovodiččovovéé laserylasery
Oxide insulation
n-AlGaAs
p+-AlGaAs (Contacting layer)
n-GaAs (Substrate)
p-GaAs (Active layer)n-AlGaAs (Confining layer)
p-AlGaAs (Confining layer)
Schematic illustration of the cross sectional structure of a buriedheterostructure laser diode.
Electrode
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
Indexom vymedzenIndexom vymedzenáášštrukttruktúúrara
(Index Guided)
Priečny rez laserovej diódy DCPB DH
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PolovodiPolovodiččovovéé laserylasery
Height, H Width W
Length, L
The laser cavity definitions and the output laser beamcharacteristics.
Fabry-Perot cavity
Dielectric mirror
Diffractionlimited laserbeam
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
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PolovodiPolovodiččovovéé laserylasery
Geometria polovodičovej laserovej diódy
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PolovodiPolovodiččovovéé laserylasery
Typical output optical power vs. diode current (I) characteristics and the correspondingoutput spectrum of a laser diode.
λ
Laser
λ
LaserOptical Power
Optical Power
I0
λ
LEDOptical Power
Ith
Spontaneousemission
Stimulatedemission
Optical Power
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
Spektrum žiarenia polovodičového lasera
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PolovodiPolovodiččovovéé laserylasery
Typical optical power output vs. forward currentfor a LED and a laser diode.
Current0
Light power Laser diode
LED
100 mA50 mA
5 mW
10 mW
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
LED a polovodičový laser – porovnanie L-I charakteristík
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PolovodiPolovodiččovovéé laserylasery
0 20 40 60 800
2
4
6
8
10
Po (mW)
I (mA)
0 °C25 °C
50 °C
Output optical power vs. diode current as three different temperatures. Thethreshold current shifts to higher temperatures.
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
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PolovodiPolovodiččovovéé laserylasery
778 780 782
Po = 1 mW
Po = 5 mW
Relative optical power
λ (nm)
Po = 3 mW
Output spectra of lasing emission from an index guided LD.At sufficiently high diode currents corresponding to highoptical power, the operation becomes single mode. (Note:Relative power scale applies to each spectrum individually andnot between spectra)
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
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PolovodiPolovodiččovovéé laserylasery
Loss
GainProfile
ν
ν
ν
LaserCavity
ExternalCavity
LaserOutput
Jednomódový polovodičový laser – princíp viazané rezonátory
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PolovodiPolovodiččovovéé laserylasery
DBR laserDBR laser
Corrugateddielectric structure
Distributed Braggreflector
(a) (b)
AB
Λ
q(λB/2n) = Λ
Active layer
(a) Distributed Bragg reflection (DBR) laser principle. (b) Partially reflected wavesat the corrugations can only constitute a reflected wave when the wavelengthsatisfies the Bragg condition. Reflected waves A and B interfere constructive whenq(λB/2n) = Λ.
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
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PolovodiPolovodiččovovéé laserylaseryDFB laserDFB laser
Λ
Active layer
Corrugated grating
Guiding layer
(a)
(a) Distributed feedback (DFB) laser structure. (b) Ideal lasing emission output. (c)Typical output spectrum from a DFB laser.
Optical power
λ (nm)
0.1 nm
Ideal lasing emission
λλ B(b) (c)
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
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PolovodiPolovodiččovovéé laserylasery
Activelayer
L D
(a)
Cleaved-coupled-cavity (C3) laser
λ
Cavity Modes
λ
λ
In L
In D
In bothL and D
(b)
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
Princip zPrincip zíískania jednomskania jednomóódoveho polovodidoveho polovodiččovovéého laseraho lasera- rozdelené rezonátory s rôznou dĺžkou
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PolovodiPolovodiččovovéé lasery lasery -- MQWMQW
A quantum well (QW) device. (a) Schematic illustration of a quantum well (QW) structure in which athin layer of GaAs is sandwiched between two wider bandgap semiconductors (AlGaAs). (b) Theconduction electrons in the GaAs layer are confined (by ² Ec) in the x-direction to a small length d sothat their energy is quantized. (c) The density of states of a two-dimensional QW. The density of statesis constant at each quantized energy level.
AlGaAs AlGaAs
GaAs
yz
x
d
Ec
Ev
d
E1
E2
E3
g(E)Density of states
E
BulkQW
n = 1
Eg2 Eg1
E n = 2² Ec
BulkQW
² Ev
(a) (b) (c)
Dy
Dz
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
hν
PolovodiPolovodiččový laser s kvantovými jamamiový laser s kvantovými jamami
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PolovodiPolovodiččovovéé lasery lasery -- MQWMQWActive layer Barrier layer
Ec
Ev
E
A multiple quantum well (MQW) structure.Electrons are injected by the forward currentinto active layers which are quantum wells.
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
PolovodiPolovodiččový laser s mnohonový laser s mnohonáásobnými kvantovými jamamisobnými kvantovými jamami
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PolovodiPolovodiččovovéé lasery lasery -- VCSELVCSEL
A simplified schematic illustration of a vertical cavitysurface emitting laser (VCSEL).
Contact
Surface emission
Dielectric mirror
Contact
Substrate
λ/4n1
Active layer
λ/4n2 Dielectric mirror
© 1999 S.O. Kasap, Optoelectronics (Prentice Hall)
Povrchovo vyPovrchovo vyžžarujarujúúci polovodici polovodiččový laserový laser
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PolovodiPolovodiččovovéé laserylasery
time
I(t) P(t)
Modulačná charakteristika LAD a časová odozva na budiaci prúdový impulz
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PolovodiPolovodiččovovéé laserylasery
VnVnúútorntornáá konkonšštrukcia laserovtrukcia laserovéého modulu so stabilizho modulu so stabilizááciou teploty a výkonuciou teploty a výkonu
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PolovodiPolovodiččovovéé laserylasery
ČČip hranovo emitujip hranovo emitujúúcej laserovej dicej laserovej dióódydy
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VýkonovVýkonovéé polovodipolovodiččovovéé laserylasery
Výkonový polovodiVýkonový polovodiččový laser ový laser –– ssúúbor laserových polbor laserových políí