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`ASML 1221
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`

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`Library at Cxmgmss Caizmgizxg-5n«§’ni:Eicxz:i<x:: Data;
`Kutm, Kalin J,
`Lass: wgiawingi Keiist J. Kuhn
`9‘
`cm.
`Includes index
`ISBN (}~02»36=692i«7 {har£i<:0ver)
`x ‘
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`I flitr.&E;a.scrs-1£:w::s~i-gn and canstmczion. 2. béaalinezr optics.
`TA1675.KBé
`F393
`9763211
`C1?
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`
`Pxintsd is the United Sterses 91" Azwexica
`13 9 3 7 ii
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`Prexxticsxffiall iitxtasrzzaéjnnal {tfxj Limii2<3,Lond:3n
`Pmnficwfiau af Augtmlia P13: ‘£.im_ited, Sydney
`Prianiicefiail Carmela Ix:c., Toremaa
`Prentiaie-§~§a§i Hi5pan0ame§'§tana, S.A., Mgxico
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`Prenticwfiaii of §apzm, Eng, Tokyo
`3?Ea&3{’S=6.’.'l ‘Sriucatiarn fissiua Pie. $321., Eingapara
`Eciitcxrz P‘:szzxté£e~I~ia§1 fix: Email, Lida‘, Rio cie}a.x2ei:s3
`
`
`
`

`
`
`
`Transitions Betwsaecu Lasts: 8:31:25, 10
`ilopuiatimz Inversion, 13
`
`Pfififfififi
`
`X1
`
`Organizatinn xi
`
`Tachxiical Eacicgmund xii
`
`Pedtagcgy
`
`xii
`
`Eeheciniing
`
`xiii
`
`Limknowiedgments
`
`xiv
`
`flats: Laser Funtéamantata
`
`3
`
`1
`
`ifiiméflfiflfififi Y6 3;..a&$§R$
`
`2
`
`1.2
`
`A Brief Histcszy
`
`2
`
`‘ 1.2
`
`The Laser Market
`
`5
`
`1.3
`
`1.4
`
`1.5
`
`1,6
`
`Enexgy fiiams in Atoms
`
`9
`
`Basic Stimulated Emissiém 10
`
`134.1
`L42
`
`Powar ami Energy
`
`14
`
`‘ Manzécizromaticizy. ilohémzcy, and Lizmwidth
`
`:5
`
`

`
`
`
`
`
`M..,-«:r;3/.:.,¢;.‘,;),,,_.,M
`
`'
`
`
`
`V‘_,..w.,-....~....~................w...«...¢,,_..m.,m:;MM,aWW,,,A..,w.....\,,,,.‘......,.,.V
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`
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`
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`"“'*"’\“‘\"“"“"“*""/-‘?'v’“"?.'m.°5°.'»...s...,.,
`
`Contains
`
`1,‘?
`
`L8.
`
`1.9
`
`. Syatiai Coherenne and Laser Sptxzkla
`
`18
`
`The {kmzfic Lamar
`
`19
`
`Transmsx: and Lsngituéinal Modes 20
`
`1.10
`
`Tim (3213:: Profile .22
`
`L11
`
`Lamr 8afnty
`
`24
`
`Symimls {ism ii: flu: Chapter
`
`25
`
`Exercises
`
`26}.
`
`9 ENERGY STAWS fiififl Gfiiifé
`
`3»?
`
`2,:
`
`35
`Energy States
`2.3.1
`Lesa: States, 35
`3,13 Mxfltigaiwszaxz Lass: Sysaams, 35
`23.3
`Lirrewidth
`the Umzeariaizxiy ikirxrsipic, 39
`2,19% Brtzaésxiizxg af Fmxisnzsezxtai 1.ia«ms2ic1ms., >41
`
`2&2
`
`Gain 43
`
`Basins af Gain, 43
`2.2.1
`22.2 Biaaiibody Rmiiafion, 4?
`2.2.3
`(}‘ain,~§5
`
`Symbuisflaad intha Ckzaptzzr
`Exercises $9
`
`ss
`
`3 3315 §¥S§.S3§"*§3§3i3?“ §’?'Ji§..(3*z9I
`
`'62
`
`3.1
`
`. 3.2
`
`Lzmgitnfiinai Matias fin the Lasgr Resonant Cavity 52
`341.1 Using an Ewan fer Sizsgie Lsngitudirml Made Oprrtatien, éé
`
`55
`Quantitative Amiysis of a Fabry-Perot Emlon
`32. 1
`Optifial W131 Rclazicms in a Fab:3e»F¢rut Etaicn, :35
`3.2.3
`Reficctioa 2122:! Transmission Coefficfiesnts in a Fa2>zy»?::rot Etalcm, 157
`3.2.’3
`Calculating the Refieeted 81143 Traxxémittad lmensixivas for 3 Fabry-Pew:
`Emlazn win: the Same Reiicavtaxsces, ’?0
`Calcufiatfmg the Refiemeé and T1"&f»:Smif£Eii Intemties for a Fa3ary«Paxot
`Estaioa wit}; ififfaxeni Reficczances, 72
`ilalcniafing the Q sari aim Fineesseof a f‘}':}}‘f}’-§3*81’t.)i Ewan, 73
`
`3.2.4
`
`3.2.5
`
`3.3
`
`Iiixssiraiiwz Fahry»’Pa.mt Etalarrz Calcislazions
`
`73
`
`Symbols Used in this Chapzar 78
`
`Exercisas
`
`‘E9
`
`

`
`vi
`
`Einnienis
`
`4 ’?°‘fiA1"J$V§:“§?§§ a§§£3£‘.T?E PRGPEfi’3*'¥£§'$
`
`83
`
`4.1
`
`4.2.
`
`4.3
`
`4.4
`
`4.5
`
`fntrodaction
`
`84
`
`8::
`TT£*IZ=siM, Transvexsée Modes
`43.2.1
`The Paraxial Apgsergmimation, 84
`4.2.2 Mafixamaxiual Treatment of the ‘lmaxverse Modes, 86
`
`TE3$’I()‘Q Gaussian Beam Fropagafim 88
`4.3.1
`The 'I'§3Mg,g car Ga1zssian_"i‘ran$vars=c Made, 88
`4.3.2
`Pmpetzies at” (has ’I‘”33i&«*I;m Mada ef the Laser, 94
`
`Ray Matxicas in Anaiyze Fwaxfial Lzms Sysimxs
`4.4.1
`Kay Matrix far a Distance :2’, 1113
`4.4.2 Ray Matrix for a Lens, KM
`43.4.3 ABC!) ‘Law Apgsiizd to Simple Lens Systcms, 108
`
`101
`
`1.10
`Gaussian Beams in Resonant Cavities
`4.5.1 Madaiing the Stability of the Laser R§$$€m:3.i€1£'.
`4.75.2 ASCD Law Apspiiexi tn Resonators, 11“?
`
`113
`
`»
`
`Symbois Us.-mi in the Chapter 122
`Exercises
`124
`
`5 Gfiifsf
`
`$»§T£§fi.&’?'¥{3?é
`
`331
`
`5.1
`
`5.2
`
`5.3
`
`133
`fiaturation of the Exgonexxziai Gain: Pmcess
`5.1.1 Gain Sauxrafiinn far tha iiamcgeanaaxs firm, 1351
`5.1.2 Gain Sanitation fear the Efiumogmmoué Lima, 1362
`5.1.3 ‘ The Ixnpariance, cf Rate’ s‘3.:;ua.€ix;xns,'134
`
`Setting Up Rate Equatiam 135
`5.2.1 Rm Equaziflm for Fsnm~Smte Laws, 237
`{agar Quipui ‘13z:me‘:*:2‘ Charactarisiics
`$43
`5.3.}
`Optima: Tilonyling, a Simgla Appmacia, $42
`5.3.2
`PM vsrsazs 1%., an Engimzeriing fipgrcach, 147
`‘ 5.3.3
`Pm; vemxs Pg,” ziaekigtmzl ispyraach, I52
`
`Symbols‘: Um! 3:’: {ha Chezptar
`
`139‘
`
`Exercises
`
`1151
`
`3 mwssam smecgssfis
`
`ms
`
`Reiaxation Oaciilatians ’ 16:83-
`§.1.1 A Quaiitative Basctiptism. af Relaxatiun {}m11a.tion:s, 15%
`5.1.2
`NBII1=E:£1°{‘.§1 Mcatieiing of Ralaxafien Osciilmiotis. 165
`6.3.3
`Arzalyticai Traatmezzi bf Rziaxaiion Qscillaiians, 171
`
`~.»k'«.«'
`
`6.}
`
`6.2
`
`-
`1??
`Q~Swit<:hin,g
`6.2.1
`A Quaii'Ea;i've Desaripiicm of Q-«Switching, 377
`
`-»
`
`
`
`

`
`
`
`Cfiantants
`
`vii
`
`$3
`
`6.4
`
`6.23 Numerical Zvioxiaiing {if Q—Swizchiz1g, 37?’
`452.3
`Ana!y£icaIT:ca'tm§n1t. of AQ«Svwitc%1i.:1g, W8
`
`182
`The Design. cf Q~Swi£sh&s
`6.3.1 Mi:=ci:axti:;8i Qsfiwimhas, 183
`6.3.2
`Eizctraogzic Qfiwitches, E84
`6.3.,3
`Q~3Vr‘§£C:hv&s, 196
`6.331
`Saitxrabie: Ahsarber Byss for Q-Swittzhing, 19}.
`
`193
`M§3£§e~L0fs2k§:zg
`.193
`6.4.1 A Quaiixazivez ikscripticsa cs? Mosie:—Locking.
`$4.2
`aixnziytisxai ifisacriptinn of TMm3sz—Lockixig, E35
`6.4.3
`'I”i:c. ifiafiign sf Mc:ciz:~L9£:1:i§::g Madulatms. 1,98
`
`Symbols Used in the Chaim: 202
`
`6.5
`
`Exercises 204
`
`§?VT§¥£3i?£!£e‘?‘.'¥{.‘!§§ ‘R3 N{3:‘3L1W‘EfiR' £?§°T7:'G$
`
`297
`
`7.1
`
`Nnnii{mar Pularizabiiiiy
`
`298
`
`7.2 . Seamxd I-iarmsmic Gemraxian ‘Z39
`?.2;1
`‘me Pracess of Cozwersiarr, 210
`12.2
`Efixasa Matchigzg, 2&5
`12,3
`‘Design fzachrfiques fin: Fmtgusncyfiloubling Laser Beams, 320
`
`‘I13
`
`7.4
`
`7.5.
`.15
`
`Ggstiaai Parametric Qsci§.¥at<ars
`
`221-
`
`Szimxziated Ramzm Scattering 226
`
`Self-Fccusing and Opiiaai Baxnaga
`Nanliaéax Crystals
`233
`7:3»: Major cxyssags, 233
`‘R53
`{)2h::r fifrystais Used in Naniinca: Gpiics, 235
`
`231
`
`Symbcis Used in the Chapter 236
`Exercises 238
`
`$£¥.¥"P08?'3r'§v’§ ?'£{?Hi¥Q!..{3G!§5
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`2%?
`
`8.1
`
`8.2
`
`8.3
`
`Imradsxctiozx 242
`
`2.42
`-Mniiilayer 9:2-a‘£$c£r§c Films
`8.2.1,
`The Fumiamentals {sf Muitilayar Fiim Theory, 2453
`8.2.2
`Afi{i~R&fi:i’€Ii¢3n Czsazings fmm Mizitiiayer Films, 245
`82.3 Highfleflectance Coatings from Mufiilayer Fiims, 248
`
`b
`
`Bireffingsnt Crystals 252
`8.3,:
`Fesizbée and Negaziva Urfiaxiai Cryavtals. 252
`3.3.2
`‘Wave Plates fromLBirafzi:2ge:12iCrysia§s, 25-4
`
`.,
`
`
`
`
`
`

`
`CI«3n$en’ts
`
`viii
`
`8.4
`
`261
`. ?§10t£3d§.‘»'£f3C{€3I’8
`84,1
`Thermal fleéetztors, 261
`344.2
`Fixotoeiwific Emission, 262
`84,3
`Pizetoconductors, 263
`3.4.4
`Junction ?h0todetecma~s, 265
`8.4.5 MOS Capacitor Devices, 268
`
`Symholsviised in ma Chapter 269
`
`Far! 3%
`
`fiasign at Law: 33.!-3:3-ms
`
`2%
`
`9 £:‘§NV£N'I?$NA:. G113 M3535
`
`27$
`
`9.}
`
`9.3
`
`274
`}{¢Nc Lasanrs
`9.1.!
`‘Hisimy atf Eieblé La.-z>:\2rs, 274
`9.1.2 Agxpiiaaticns fer fiézfie Lasers, $26
`29.1.3
`Tm: fiefle Enezrgy States, 23$}
`9.1.4 Design of 2; Maxim: Commarcial we Lascs, 283
`
`I
`338
`Asgun Lasers
`9.2.1
`iiistory of Argon» and Krypton-ion Laaers, 289
`912.2 Apgziicatiaas fer Argana anti Evixygszcarvion Lasers, 25%)
`9.2.3 Argan and Kryptan Law Statex. 292
`9.24 Design of :3 Medan: Cernmszcial Argon-Ian Laser. 394
`
`Exaraises 380
`
`75 €?£3‘3‘4§/E'i‘J3’?%'3s’fi€.e<3.£.
`
`8€?£..!fi»3‘i".é?'§' Ls4$£F?$
`
`333
`
`29.1
`
`18.2
`10.3
`
`303
`
`30’?
`Apygiicatizms
`.Lase:r Mamxiais 308
`19.3.1 Crysmiiine Lxsar H0338, 3&9
`1(}.3‘2 Glass Laser 803:3, 31%?
`10.3.3 The Shag: cf the Salixifitmse Laser Materiai, 313
`
`10.4
`
`The Lasar Transiiitm In Nd:YAG 312
`
`163.5
`
`Rump Txachnelogy‘ 315
`iO‘§.1 bioblc Cias Discharge Lamps as Ogticai §’um§> Sevurces far N:§:YAG
`Lascm 316
`‘
`
`103.2 Fswar sapplias far Ncsbie: Gas Discharge Lamps, 321
`10.5.3 Pam}: Cavitias for riobkz Gas Disaharga Lam?-Pazmgwd Laws, 32%
`10.5.4 S;;a:’.-¥m~?i2ys§cs (2umta~8ay GCR Famiiy, 327
`10.5.5 Sxzzmicomziucmr Lasaxs as .so1ié»sme 1.a3l:r Pump Soxxmas, 329
`10,16 Fm:z§ Cavities {or made Lassr Fumped ,8oIid~Statc Lasers, 333
`10.5.7 Cohzzrent B938 3064 ‘Laser Famiiy, 337
`Exercises
`333
`
`
`
`

`
`
`
`Cmtezm
`
`3‘? ?”fi'.%fia‘Sf??0?hf~1§»§;E?".&1L 3£3i.¥£?~$7}§‘1'°aE' £..2§S£“R3
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`3:34
`
`11.1
`
`13.2
`
`11.3
`
`11.33
`
`U5
`
`iiismry 345
`
`3:38
`Apyficazims
`Lesa: kviaémials
`348
`13.3.1 Rnbywfrimary Lime at 694.3 um, 349
`13.3.2 A}exam:%:ite-«~Tm1ab1e imam 'i‘0£1 nm ‘to 813 mm, 351
`1'§.3,3 ’I"i:Sapp}:§:re—-'fa:r:ab1e fmm 67$ mm is: 3091) max, 353
`11.3.4 Csmpaxison batsman Ikiagczvr Sazlisiszate 3.»&S*i‘t iilnsts, 355
`
`"ri:s.a;;pmm Lam Basign
`11.4.1 Rissg Laaem. 355 '
`'
`11.5.2 Bimfringem Fiimrs, 3&2
`.1 1313.3 Cohexant Model ‘$90 and 899 Tftfiagrphitt Lxarers, 365
`
`355
`
`3'20
`Fcmtosacxzmd. Fxxise Laser mzségn
`11.5.1 i}is3;mf?.'icx:: in Fzmmsacézmsé Lama $30
`~ 31.5.2
`¥\Itsa%irma:i1ies’Us¢d to {flame Famaasecmwd msim, ?{;‘1
`11.53
`M::asx2:ris1g Femtqsecnnd Faises; 3??
`115.4
`Caiiiaiing fisiss Mafiwhuckfing, 373
`12.5.5
`fimtksg Piflsa Cempressinn, 3’?4
`11535
`fixilitsansg 37.3
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`11.5.”?
`Kz:rr~Le.ns M£>1§@»I.t>cki::g {i<Zi.M) in Ti:$spp.¥1ir~:. 376.
`Comxastt Mira Femmseconcl Lasars, .31’?
`11.3.8
`
`'
`
`Exercises
`
`380
`
`3‘? Qfiififi‘ Mfidflfi GOM!9¥&'R€§A£
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`§...§$ER$
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`3813
`
`12;}.
`
`12.2
`
`12.3
`
`The ?C)esi,gn of Carbon flisxide Lasers 385
`12.1.3 ,In1ms;i:1ction :6 C0; Laser Simes, 386
`12.1.2 The Evolxtfiaa cf C0; Lasasis, 389
`12.1.3 3rV£iVE‘.gfli(¥E {Sm Lasexs’. 393
`12.1.4 A Tygzical Medan CG; Kndxzszziai Law“, 3913-
`12.l.§ fiépfical Components and fietemom for Cf}; Lasers, 403
`
`The Bzsign af Excimer Lasers 4%
`12.2.1 Irmodxxctiun £9 Eixcimaer Last: $:a.ies., 405
`12.2.2 The iivolution of Excixrms, 403
`32.2.3 Ct'8€¥2§;$2‘33 Dmign B&c1<gmu11éi.,4i}9
`12.2.4 & Tygiical Madam Excimar Laser, 414
`12.2.5 Laser fieam Hnmogenisaers, 417
`12.2.6 2-‘xppiicatian Highlight 418
`
`42}
`{Zwerview of Seamicoxxiuctczr Dicda Lassrs
`12.3.1 Histtsry ‘sf Sezxxic.-cm<iuc=tor Diogie. Lasers, 421
`12.3.2 The Basics cf the Ssmicsmductor 9306: Laser, 424*»
`12.3.3 Coafintzmsm in the Sszmiconductor Diode Laser, $238
`12.3.4 The Qxmnmrn ‘wsii Szsmizsmnizzctcz Died: Laser, 432
`12.3.5 Application Highiight: The CD Player, 6335
`
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`1%.?
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`2&3
`
`2&4
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`3&5
`
`A13
`
`A31
`
`441
`Lasar Safety
`A.1.‘1
`Eicctamuxian, 441
`A.1.2 Eye Damage, 444
`A.I,3 Chemical Hazards, 446
`A,.i.4 Other Hazaxés. 447
`
`Significaxxt Figures‘ 450
`
`‘I136 Elestramagmfic Wave Equation 45$}
`Ay3.1 MaxweiI’s Equations, 450
`5.3.3 A Gama! Wava Equation far Light Pmpagaticn in a Eviazerial. 452
`. A33 Lig¥zt‘£’ro;311ga£iGnh1 2: Vacuum, 453
`A.3.4 Light Pmgpagaticn in a Simgzle Isotmgic Maxezéal with No Net Static
`Charga, 451$
`Ligjfxt Propagafien in 3 Sim}: Laser Mat::ia3 with Na Na? Emtic
`Cizatgm 454
`$3.5 A Dxwnimansienai Wave Eiquaxicn far a Lass Simple Iscmopic
`Bséaistiai, 4&4
`
`A.3.5
`
`Lcznscs arid ‘faiascagas
`AIL}
`Lansaas. 4:56
`13.4.2
`.(ZԤassica1 Lens Ecguations. 437
`A33 Teimww, 459
`
`456
`
`Refiactien and Rafxzacfian 461
`ASA hiemenciatzxze, 461
`A..5.2
`Szxews Law. 4&2
`A,5.3 was intexzzai Rezfiezztion, 462
`$5.4 £§mwsIs:r’s Angie, 4352
`
`Fresnel Equziiens
`
`463
`
`T225 ‘£iffe><:tivs Value cf zhs: Naniinaar Team:
`
`465»
`
`A3 mime ami Ifiesign Activities 466
`A.8,1 Gas
`Mtivizies, 456
`A.§i.2
`Z%E<§:’§’Ai§ Laser Astivifias, 4??
`$3.3 ’§‘razzsiti«:m M:::a13Las£r Activities, 4'33
`$8.4 Suxmssfnl. Smézxat Pragezzts, 4'34
`
`A;€¥
`
`Lasar z3.iig1m5zi£ 475
`
`Ali) Glussary of Basis: Lam‘ Tezsazs
`
`47’?
`
`iE‘£9EX
`
`4%
`
`#3Q%*§$?}§.N3"3 é2'S£'$ £83 BG~£'.3K
`
`£98
`
`
`
`

`
`
`
` Transifion~Mefai
`Solid -Sfafe Losers
`
`Objectives ’
`
`e To summariza the sequexxca of historig::a1 events leading to the development of rifle’
`£ransition~meia]. Sflfidrgffité laser.
`'
`’
`
`a To summarize commerciai appiications for *transiti0n~n1eia1 so3id~state ‘lasers.
`
`0 ‘TF0 Acoxnpam and contrast the energy band stmciura anti .major faser Lpmpmies ft; ._
`the -primary sammeirdal :~mIid«stat_e laser materials {ruby}, gaiexandriie,
`'I‘i:sapphirs,_
`LNd;YA¢:.}.
`_
`~
`9 T0 describe the design (if ring laser cavities.
`
`o T9 compare; and contrast ring laser cavities with linear cav’itic~s.
`a To describe tha impartance, uf bi7refri ngent fiiters.
`a To compu’te'tfi§. intensity t1'2m‘smiita'nce for a birefringent filter.
`a To describe1:h;e'c;3nstruc:ioi1 of a.co.n_1me1'cia1 1ase.rpmnped é:»011tinu0'I_1S wave:'.I‘ri:sapphi.:~e
`laser,
`
`9 T9 describe. the! design principles unxmrlying faxntosecond pulse laser design, This
`would inciude such .issue:.s as group ‘V=e1oc:i;y' dispersion (GVD), seIf~p’hase .modu,1a~
`tion (SPM), femtosecoixd pulse temporal measure_ment,‘co13iding pulse niodedocking‘
`(CPM), grating pu1s_e»c::m1px'ession, solitons, and I{er:*~1en‘s nmdwlocking (KLM).
`_
`
`a To describe the co.nstrucIi_on' of a cemmerciai u1iz'ashoz:tAp'u1se Tizsapphire lasex‘, ,
`
`‘E3
`>2;
`
`:§,
`
`344 ‘
`
`

`
`Sec. 11.1
`
`History
`
`345
`
`
`
`The transifion~1nef2s,l salm-
`. Fi'gu1':j: 11.1
`sxzltc tunable lasers use metais in the fourth
`rmv cf the ];:e.rikJdie.: {able as. the z1s:t§‘ve
`ions. Ttxszeaz ;neiais,::;a1; pmduce ‘trzx-zisitiqns
`that inwmivi-2 phomms as welt as phmons
`fiofzen cafled vibronk’: or p11onoI1'-t::rmi11atcd
`{$2‘msiti0ns)A_ Such tmus1tiQ:1s san curate
`in11a1>Ie4fb111'«‘les'ai Ilaser be-lmvior;
`
`‘i ‘L1 MSTORY
`
`V
`
`.F;;;-
`Tile hismry of tra11si§ion—':11eta1 s.o’Iic1-state txxnabie iasers is ex.cepti-_<m.a'i1y faszrixmting.
`the: HeNe, a1‘gon»-ion zinc? Nd:’YAG Iiasers (ieventhe diode pu111;7e<i Nd':YAG iasmtsz) the
`majority cf the laser science was in piace by the mid«’I960s anti ssonumcrcial deveiopmem
`proceeded rapidiy after that. T1'a11sition~meIa1 tunable soiidastate lasers are quite £i.ii”Ya’:'en£.
`Tra:1sit'ion*:neia1 II}I1<‘3b1€!’S€}H'd~SI21{€:1i1.'i81‘S
`are bmiy n2e.uAti<:med in rczxsiew papers on umabir:
`1ase;' techn<al~x::gy
`‘1f€:C€I1i}}{
`as 1982.‘
`'
`.
`‘
`’i‘i:sapphiz'e .2:-users {the cumtni stars of me mlidmaizz tmxabie mast‘ znarket) were discsw
`erad b}z»Mm1I_tonbin iI9€?>‘3.3
`'fi{:we'ver, cariy resuits with '£’i:.s21;2phir<s: wars not pmxnising due
`:0 difficuliieziwith mareriai gtmvth} If W1-3.‘5 mxiy after ‘iha .ma£ar§aIs probieins were sawed
`that the true potential af tha *IԤ:sa;)pf1im '_iz:5'ar was reatized. As: a colgseqmxxce, much of
`the Iaser devesigvpment {inciutiirxg the n2;nas*}<abia se}:f~:nacie~}x:>c.§:ing prepwsies of Titsapphiuz
`dVi.sc:ussad in Secticm 11.5) hag csecurred 1'e¥a{ive1y recenify‘.
`The tra:1siti’ox1~‘m<:£zz1 soiid«smta, tunabie lasers 133125 meial-3 in thefi faurth mw of the
`periodic ‘table as the active ions. The'transiti0n~n1e£za1i$ have a pzmially {flied 36 Shell, and
`the vzarious observed mmsitizms occur‘ near this :.<;he.iI.. 3d aiecérozzs interact mom strongly
`with the crystai field than the 4Vf’e‘lectx'o11's in canwzxxtional solidestate 1asers:suchL as .Nd:’YAG,
`This can pmduce transitions that involve’: phonons as wet] as photans {often <:.al§ed vihroziiz:
`or phonon~-terxni11at<:d t-ransétions). Such transitions am rather psca1Iia.r§ as. they can ;:reat<~:
`fiCIL’1.i‘~§£‘J£’€3}
`las¢:1‘be.h;w~iar bxatweexz two level Imnsit.ion:s,
`schematic of a vvibmnic trzmsition
`
`,
`,
`is ilimzimmd in Figzare 11.1.
`In at vib;'£mic tnmsiticsn an optical photon is used to make the transiticxn froxn the ground
`state tn the pump state, Then the ak2ct1'm1 decays tn the upper laser state by mleéwing as
`phonon (an acousticzai quanta simiiar to -a pmyton). The laser aciion oceans betweaaz the upper
`and kwwcr ‘l2ise1"As:€;tc:s. The lower laser state than decays to ‘£116 gronml state by iéieasiilg
`
`J‘. af‘Qiz(mIu121 Efzclrmz. QE—13:£ 179 (1.983)
`"B. D. Ciuenthzer and ‘R. G. Buscr,
`3?. F. Moulmn, Srziizl Sims Resemclx. 1€a,::orz, DTIC A'D».€3.Lf2~¥3(?3f4 (I982:3) (Lexington: MIT Lincoln. 1,321.,
`198:2), 91% 15~21.
`-‘P. Lacovzxra am! "L. Iisterowitzk IEEE J. ofQ:,:xz1mzm Z*£!<_:z:!mz:. QE~21:'16}-’$ >{'193S).»
`
`

`
`346
`
`~
`
`'
`
`Transitio'n»~MetaI S.olicl~Sia’te Lasers
`
`Chap. M _
`
`another phonon. Thus, founstate laser behavior is obtained from a system that is effectively
`two-state. More importantly, since a wide‘ va1*iet:_y of phonon tljansitiens are possible, the
`upper and ,lmver»1aser smtes; consist of large manifolds of states. Therefore. highly tunable
`laser action is poss.ib.1e.
`.
`The fi1‘stvibm’nic §aser\vas*1'eported by lc>h.n:=;m1et_ 3}. at Bell. Labomtmiies .in 1963.4
`It was a divalént u:ans.i{.ion‘»:netai. 32136;‘ ‘using Ni” in M‘gFg. it stimulated some early xx/mjk
`by Mc:Cumbe:‘ in the t_h.e0ry of Lvibronic lasers? Hewever, it was cryogenically cooled and
`did not excite much commercial itaterest.
`
`Fzxzither effparts by Jalmsim and his colleagues duritgg the mid to late £9609. x'esz11ted in.
`s<:ver:al mare cryeganically coaied divvallent tra1§sition~meta.1 lasers. These included Co“ in
`- Mgifi. and-“V24” in Mg}2g_.6
`.
`A major advancement occurred in 1976 when Morris and Clirxé’ obse;"s€c:d that allexam
`{kite {BeAl2().;:Cz'3*’ Q1: gzhmmium doped chsysizbexyi,
`tunable fmm 700 nm u) 818 mm)
`would ‘lass on $1'vi¥:>mnic't.ran:“siLic)n. "Walling at al. {;0‘:1§.r1nedthese results alTzd,d€i‘11Q11S{x‘zlt€d
`Q-switching behavior.” Aiexandrite. was; pal’-ticularly interesting at the time of its .dis<:o.v~ .
`‘ .<;2'y because it iasexi 21: team temperatum and inereawti in outgaut po‘.wE:r as the tcanperatme
`in‘cre:ased.9
`_
`'
`The succéssfui me at’ Cr” in a hazy! crystal. had to several <)thex'-inte1'eSiing’Vi'bmnic
`‘lasers.
`In particalar, in 1982 Shani! and Walling,” and i‘nd3pendan£¥y 'Buc}1e1“£ er 211;,”
`slxowed that exnemlkit (§3.e3AI2(SiE)3):C:‘3*, another type. of c:§1rc::i1iu.:n~d0;:ed cihrysobexiyi and
`tunable from roughly‘ 3'09 mm to 860 am} would laser as 3 vibrallic. 12156: at mam tmnpemtxzre.
`C§3r0mi—un1'waS ai5§i§.f£)L1lI£3‘3;0 generate vib_r0ni:s2 laser _parf<:¥riI1ar:c€
`in gzaduliniunu scazldiusn
`gallium game: {$3363.33 >
`.
`A
`'
`<
`.
`'
`.Thx=:se encoiz.mg.ing results; in (:hr0mium—d0ped zn.£¥le.rial.$ led ‘to a rebirth in tunable
`s;oiid~s’tate laser research. Tizsapphire fihe cmwn jaw’: of modem umab’le so'Iid*:ztate.~lasers)
`
`I. Gxtgganheilnn. I’2’z3>s. Raw, Let¥. H1318 (1963).
`‘L. F. Iolmsrm, R. €.'IZii.r:{2, and
`51}. ii. McCu1n7i_x:‘r, P}13*»5'.‘li8x'.
`l34:A2§9 (!£_i64~}_: 2). E. i\ricCumbe?, J. Mrztfz. Phys. 5:508 ’( l96<3}; and II). E.
`"M<:Cmnbe't, Phys, Rev. 336:A’952l £19653);
`'
`'
`”
`
`6L. F. 3‘ahns<1n, R. E. Diem, and H. I. Guggenlleian, App}. Pfgvs. Lexi. 5:21 (i’§)15=l); L. F. 3611113031 and H. J.
`fiiuggenheinx, J. A3321. F2153. 3l3:4l§3'I {1967};1..F.J'ahnsnn and H;I.€}11ggcx1I1eim, J. Appl. Plzyx. 38:48’37 (3.957); .
`-and L. F. 3'oIn1's»<:m,i~¥. 3. Gugganlmim and R; :’&."I‘h0n121s, Phys, 123:’. 149:179 (1966,).
`"R. C, Mzmis and._{2. F. Cline, “Clh1‘L)rniu1I!~DL>pcd Beryllixrnm g‘dnmi’nme I.as:ars;" (3.3. P:m:nt,#3,§97.853,
`Use. 14, "1976.
`f
`’
`_
`.
`‘
`
`C. Morris, ‘:3. W. 0‘Dell, and O. G. Peterson. Anmml meeting Opt. Sci.
`-31;. C, Walling. H; F;,_Jc:assen,
`.
`Amaxz, Sim F1‘ancisc;3, CA, 1978: 3. C. Walling, H. P. Brmssm. R. (3. Moms. ‘W. 0‘I}el1, zu1d‘G, Peiecson, Clpi.
`L911, 4:182 »{ 19393 3. C. VValIi;_xg, (3, G. Peterson, H. P. Jensscn, R. C. Morris, and W. 0’Del1, IEEE J. Quaufwn
`Eiemzzrz. Ql?S—l6,:13£)2 (1980); Land C. L, Sam. 1. C. Waiting, I:-1'. P.3<m$scx1. R. C. Moms, and E. W. O’Dc'Il_, PI-ac;
`Soc. I’I1o!o~§}pI. Iszsr, Eng. {S'P1‘1E’) ‘?217:l30 (1980).
`’
`-
`“M”. L, Shad zrncl H. Jcittseiarx, IEIEE J. rzf Qugmfzzm Elecwzm. QE~19:<380 {.1933}.
`mivfi. Shal1d'm1r}'3.'Wa1ling, IEEE J. of Qnrmmm .I:"?ecmm. QIE~].8:I829 (1982).
`”J',Buv:l1en,A. Km, and R. R, Alfano, 12:5}; J. of Quanlzmz zazecxz-an. QE~19:l477 £1933).
`‘ZR. V. Zharikov, N. N. ll’iche—v, S. P. Kaltin, V. "V. Laptcv, A. A. Malyutin, V. V. Osiko, V. G. Osrroumov,
`P. I’. Paslainim A. M, f’r<Si<h<:mv, V. A. Smimov, A. F. Umyslmv, and I. A. Shcherbzxkov, Emé. J. Qmummz Elecrrron,
`133274 (1983).
`‘
`
`

`
`Sec. 11.22
`
`Appfications
`
`34? '
`
`was Cliscovérccl in 1982 by 1‘vi<.>‘u.1t0n at MIT Lincoln Labs.” Aithough sz1pphi.re.is that oidesst
`laser material {ruby is (‘$173+ in zgapphire) the discovery of the lnxrtmdly tunable nalure of Ti“
`in sapphimwas quite unexpected, A review report on tunable so.1id~state lasers pubIi.<;h<:d in
`198?.” and a review paper on aIAex.andrii‘e lasers in 19.85” do not <—:v<~:n-mention Tizsapphins.
`4 Part of the deiay in Ti:sapphire ‘emerging as a viabie cmmnercial tux1ab}e‘solid«state
`lasar was inatezials~bzzsed.
`.Barl'y 'I‘i:sappl1‘ix*e crystals showed an absmption at the lasing
`wave1engt,I1s that was appmximately an order of _magnitude higher than the absoxrption in
`highvquaiixy sapph‘ire. A number of pcmible dezfects were propessdlfi and a1.‘tcr.rnuch inves-
`tigation the residual absm“ptien Vin. ~vs:ticz1i—gradir3nt~f1~aeze (V61?) :crysta1s was shown to be
`due to quadrupiy ionized ti£_auium {’I‘i‘”‘) substituting for the aluminum in ‘the. $é3pphi1”€.”’iS’
`G1‘<)wt'h.a'nd anxleaiixig methods have significantfiiy reduced this pmbieamt in moxiem com,naer-
`C5211 'I‘i:sa;_3p.hire mat£:ri—ai.,
`In spite of its many advantages, T:i:Sapphim‘doeSA suffer ffmm a_ few c'iis.advan:tages. In
`particniar, its shod upper state 1ifz:time(3,2 us) makes it quite difficzuis; in pump with a lamp,
`Aitfwugh §amp'-pumfzed ’I‘i:sapphi1':2 lasers have been 'buiit,“’ most comnaerciai ‘I’.i:sap'phirc
`lasers are pumped with zxrg:>n—i0n or vclcztzbied Nd:YAG iasexs.
`V
`Several other materials have seen some connncr<:i211_i11£e.1'est as posgibie iamp pumped
`laser nxatariais. infipmicular 1.iCz1A.1.‘£~Q;:'Cr3§“ and LiS:¢A1.F5:Cr3’*‘ havaseen mm: interest as
`possible £un.a33§e camxnmacizil laser sou1‘ce.s.2" A number of aches‘ c:i1mI11iu1n~dopr::d Inamriais
`including Cr:forsier.ite and Cr:YA(3 are aim showing strong potemia1.2‘
`Transi{ion~n1e.taI saxiidasiaira zunabie iascrs am still being acfivaiy developed. Barnes”
`and Budger er. 211.33 pmvide goo-ti cwezrview tmatments of this tieveiaping fieki.
`in addition,
`there arcs three specizzi issues: in IEEE journals on iunabie iasersfé
`
`‘E9. 1“. Nioufttm, Solfd’ Sta-.z‘£: Rmaxrrciz Regan. DTKC ADA124305/4 (I9'82:3)v(MIT.L?ncoh1 i.z§b., Lexingttm-,
`1982), pp,
`15-21, repm-ted by 3?.
`Moulmn, “.Rec::.m Ativances. in Solid-Slate Lmgers.” Pros. Can. 1.aser.s
`}§ft:‘€fm«0pf., Anal}:-311:, CA. 1984, paper WA2.
`,
`
`J.‘ ¢:j’QuauIztng .¥:‘1»2cf_rw2. QB-18:l1?9 {N382},
`“B. B, Guaxxlher and R. £3. Buser,
`*5}. C, Wa11i.ng,.D». F. Hellex, H. Samuelson, 13.. J. Harm‘, J. A. 134213, {mt} E. C. Morris, 1588!; rzf Qttwtrnm
`Eieclmrz. Q_Ev‘2i:1568 (1985).
`‘GP. Laeovam and L. Estemwitz, 15:5}: J; 9; Qzmnmm zs1mm»z. QB32 141614 (11985).
`
`”A..Sanc¥1m:, A. 3.» Strzmss, ‘R. L. Agga’rss?.aL and R. Ii. ¥?ahay, 1858 J. <2fQtta1ztu::zE3z!€rz‘z'>11} 241995 (1983).
`“IR. Aggzuwal, A. Saxtciiez, M. Siuppi, "R. Fahey, A, Smmss, W. Rapoport. and C, Khanak,
`J, 12!‘
`Qwrmzum I-ZIe'-<:tn:m. 2:$:1{i(}3 (1938).
`“P. Lacovara, I.‘ Esteroxvitz and R. Allen, Dpr. Len. 10:37} 0985}.
`30.8. A. 'Pa'yut:, L. L; Chase, B. W. Nkswkirk, L. K.A3mith,-m1d W. F, iiirupkn, IEEE J. cf Qua/1_mz2z* Elecirarz.
`343243 (1988); and 3.. A. Fame, L, L. Chase, L. "K. smith, W. L. Kway; and H; W. 'N"cxvk’irk, J,_AppI. Plum.
`66:185.} (1989)
`"
`i262 (1995).
`'l'0pirs in Qumzlum Elecrrtm.
`“C. I’oI1m:k., "D.
`'B»z£gber, J. ‘MESS;-alld S, .Ma1}<.ga‘zxf, IEE131 of5561.
`z3Norm:.m P.
`]3z11'11e;§, ‘Transition Mata] Solid State Lasers,” in Twzrzbfe Lzzxem Hamiimok, ed F. J. Dmu-t«:
`‘ (San Ibiegzxz Acad¢mic }“.a'e:2;s, 1995),
`33 A, B1xd_‘gor, L‘ Esmroxvxiz. and L. G, I:)x‘:S1x:1zm', eds;.'1'um1b1'e Solid Smre L{I.‘§é‘i‘.§‘ I1 {B,erIin‘:' Springer Ver]ag,,
`1986).
`-
`-
`
`3"IEE£i' J. of Qmmrmn Elecmm. QE~l8 (3982); QE~2»l
`i.i’Iec:m)n. C1995).
`
`(19851: and
`
`J. of Se],
`
`i‘":71)iL’$ in Qmuztzmv
`
`

`
`348
`
`.v
`
`Transition~MetaI Solld—Stale Lasers
`
`Chap. 11
`
`1-1.2 Apm.:c;A'rt0N7s
`
`Transiticm~metal s-o1‘id»state u1nab.l<:.1asers provide two major featm‘es. First, they are tunable
`ovcz'ab1:<>ad range of visible and nea1‘IR wavelengths. Second, they can "bra used to procluce
`extramely "short pufisss.
`‘
`The ltunability feature means that these: lasers are icieal. for speczimscopic applications.
`This nm‘ only invlxxcies traditional saientific spectroscopy, but also ‘medical dizlgnostic spec»
`trosc.o_py.. For example, Ti::.»rappI1ix'e ‘lasers inwe b..e=e.n used to perform an optical version of
`conventional maxnm.ography.25 'I‘here -are alse potentéal applicatmns for absorption, Raman,
`ant} fluorescence sprzctzmzassopy in meciical i’n1aging.2"’
`SoIid~sta£¢: lasers czmnpefiz. with dye lasers far medicai applications 1'equ3ri:1g bath
`mnabiiity and .i11:ens§ty. Priznary ammxg these are cosmetic surgery for port-‘wine birtllmarks,
`telangiectasia, warts, stretch marks, acne scars, re’moving taztoos, and psoriasis.” Tunable
`sol.id~:s_tat’:: lasers also compete; Wiifi (1% lasers for mrecfical apygiications such M s‘hattering
`.k.ic‘mey stcn1€:s.,3x
`"
`,
`In additima’,
`the ssxtrelxxely s31or§. _pu¥se;<; possil3’le with {unable so'lid~s’tate "lasers are
`finding appl.icati0I1 in micmnzachining. ’F<:mtasece11d»pulsed Tizsapphire. lasers can be used
`for micrt>1nach.ining hula: in snetzill Aamcl ‘polymer sutastrates as well as for abljating pho~
`tczresist films and cutting f1‘2l§3€’:S on se1nico11{lm:tor 1naterials.39 Titmpphire [lasers compete
`with Nd:YAG, ciiodeqzuxngged 3N6:YAG, and excimer ilasars for this extra;-mly important
`znarkei.
`'
`«
`=
`‘
`'
`
`11.3 L9‘-\3§R Mfi.TEF§iAL$
`
`Ruby, ‘akvzandrita, and Tizsapphire are the Illfljfif transitioxmxetzii soiisimxate: l£!se;1' materials.
`Altlmugh why is -nut used emzxmmtialely
`a.Ttzxna:b1ta lasar; 3% does have a mxmble v:it3.r<:~1xi-::
`transi.ti'on., Interestingly enough, the ‘band struc:ture czf alexzxnclrite is quite .simi1ar ta -ruby;
`_ except in a1lexan;:l.:‘i‘t:: the xzibmxxic tm.ns.it'i0n is this imparlant (me mad 8:: namrzw line iransitiorr
`is not used. ' 111 coxltrasi, Titsappifirfz has crysiallime axxdxxiecixanficval properties virtuaiiy.
`.identica1 ta ruby, but a draxxxaiically ciiffment band stmcmre.
`:
`A number of pub'li<:ax:imzs cal: provide additigmal infomtaiion ‘fer the in’t£rested tezstiexf.
`O.ve.1‘View Irezmnenis are givtf-:11 by Wc3b::r,3° Koechnm;3‘_ an:i"{Zmar£e,33 whiia ’n1o1"a specific
`
`T
`
`"’~‘I,rzs«2’ I“m.-xix l.§;c{r1(I, Feb; .38 (1996).
`35£ase*r Focus world, Feb; 72 (1995).
`27La.s‘z>.r Fmsus l-i"ori’r1,. 1‘vf2ty': 6647 (1996),
`ifizam I-"o.cu.$ Wm-‘rd, May: 6631 (1996).
`29Lnxe2‘ Fr):-us Wm-Id, January: 22 (1996).
`3"i\’}a1‘vil: J". Weber, -ed, Harzdfzoaic 43]‘ I,¢1.s‘cr 5’r::'{2:zc¢' m2c¥’I'z:c11rzalczgy, Va-I. I,-Lcwerx (::zc'U*e:f;1se1's (150113 I~’.;’x£,0n,
`FL: CRC .P;'e5:‘<. I.nc,, 1982.); and more nwsntiy, Marvin J. Weber. ed, H¢m.n'[_2ook qflcrxer .S'cie:ztxe r1r,zdTec1zzzaI<2g31,
`S::1;;z?e1:z.enI I, Lasers (Boca Raton, F.¥...: CRC ,Px'c3s>:,- Incl,
`IQSJI}.
`3’\Valtm’ K(“2v€(Ihl1(t)’._ Solid Stale .l.aser Ezzgizrewirzg‘, 4th ed, (Berlin: Springcl'-Vc~rlag, 1996).
`
`

`
`‘Sec, 11,3
`
`Laser Materials
`
`A
`
`V
`
`349
`
`ruby.
`
`Figure 11.2
`
`The energy band diagraxn for
`
`information can be obtained fmrn the Wide variety of review papers on a1ex,andrite35 and
`'I‘i»:sa_pphire.34+35 Manufacturer data sheets and application notes are also very usefui.”
`
`' 11.3.3‘ Ruisy-«Primary :..ine=.»a:.a94.3 hm
`
`Ruby .(chromium—d0ped A1293} is a red or pink hexagfinal crystal whose maxi fanfiiiar app1i~
`cation is jeweiry. Ruby is an opticaily uniaxial cry31a¥37 that is hard {EX/IQh’s hardness cf 9),
`of gwd ep1i<:a’1qua’Ii.ty, and extremely thermally mmfiuctive (0.42 W'!cm«K at 380K). Ruby is
`vnoxiirygroscuyie, 1*efracw:y, anti -is gcxmmfly -cO!’1Si{§e{i3£'1 the mam’ ziurabie of {I15 common laser
`crystals {with the peossibie: exmzption 9:? Tizsapphire). Ruby erystais are typically grown by me.
`.€L‘.zoc;hra§sk’i method {the saM1ne’me€§md_as used fur the gmwtix of Siiiflfifi}; Ruby can he gmwn
`at 0,, 60, or 90 degrees tome tsptic axis, and laser material is usuaiiy gxtawxt at 60 degrees.
`Sapphire "is doped with C‘r3““ to: obtain ruby. The 'Cr3“" substitutes far the A}3+ in tha
`crystal. Typicai. dopings are 0.05 waight percent of C1203. Hoxvever, excess chromium can
`distort. the crystal structure anzi‘coneerztr’at.i<znsA'are sometimes reduced to 6:03 weight pament
`ta enhzmce the opticai beam quaiityt
`The energy diagram far ruby is givan in Figure: 11.2, Ruby is ‘th.ree‘~s,Iate fanii is that
`oniy commercially viable three-«state iaser system The Iasar pump bands are prirmpaliy
`that ”F; and ’the;4Fg bauds. The: gmmfxd state is the ‘A2 haxxd. The Iwa pump bands form
`manifolds centered. around the biue, €400 nm) anclgreen {555 nm). The pump bands are
`
`,
`“F. J. Duane ed, ..7’zmrzl71‘_’e Lasers Haz2dbaok(Sax1 Diego; Academic. Yress 1995).
`“J. C. Walling,‘ D. F. Heller, H, Same-.1,so.n; :3. J. Harm‘, 1, A. ‘Pete, and R. c. Mom's, 2322131. af Qua/ztznn.
`f:ZIe::£mI:. QB.-2121558 (.1985).
`“A. Sfincfxez., A. 1'. Sixm1.ss, R, L. Aggarwal, zmd,R’. E. Palm}.-3.1. of Qumzlzrrn EleC;‘rr7n. 24995 (L988).
`3512. Aggarwal, A, Sanchez, M; smppi‘, R. Fahey, A. Stmuss, w. Rapmpom and c. Khzmak, II52'1E.l. of
`- Qz.1m2IzgI:zEle<:fro11, 2£1CfI0G3' (1983),
`»
`’
`363./lajor
`é:'ty‘s{€I§
`suppiiets are Union Carbide (ruby, alelxnndrite and Tizsapphire) and Litmn Airimn
`-(ztlexzxndriié).
`‘
`
`“A uniaxial crystal is one where: two «.1? the Canesian directians have one index of ,refra<:tio_n '10 and the third.
`has a different index of refraction 42¢. See: Section 8.3 for 21, di$c11~zsSio;) of uniaxial and biaxial crystals,
`
`

`
`350
`
`1
`
`.
`
`Transitionwletél Soiid~Siate Lasers
`
`Chap. H
`
`each. quite wide, with £he~blue.ba11d about 0.05 microns wide and the green band about 0.07
`microns wide.
`’
`‘
`‘
`
`The lifetime in the pump bands is extremely short, with the ions cascading almost
`immediately totho metastable 33‘ states. The 'u_ppe.r 2!? state is termed the 2X state and the
`lower is termed the 73 state. The 235 and 2: states are separated by 29 em"‘, which gives
`a population. yatio at thermal equifibrium, of 87%. Thus,» while fluorescence in ruby occurs
`from both the 23: state to the "A3 (tanned the "R2 transition at 692.9 nm) and from the E7
`state to the “Ag (termed_ the Re, mansitiorx at 694.3 nm), laser action firs: occurs on the R1
`1ra'nsi1ion. Qnce‘ laser action‘ has begun, we rapid r4:-.Iaxatio11 time from the '2}? in the 7*?
`transition. prohibits laser action starting on the Kg line. The only way to start faser action.
`on the R; ‘line is to suppress the R} Iineby special dielectric coated mirrors or internal
`cavity ebsorisers,
`(Interesting enough, even though 1.asing_ cszcurs primarily on. the R; and
`R; 11:163., sidebaxlds have been observeci on the long wavelength side, in pax'tiéuIa1' at 767
`no}, attribuxed to vibronic lasing.)
`V
`T
`Since ruby is uniaxial, its absorgation coefficient is. a_ very strontg‘ funetioxi of the po~
`iarization ciirection of the Eight (see Figure 11.3). This property ssgrongiye affects the be-anl
`,;..gusIi:y;
`‘The best optical quaiity‘ ruby is grown with :he crystal axis at 60 degrees to the
`boots axis. When such a ruby rod is pumped in a diffuse refiecting pump cavity, pump
`Iightjparailel to the oasis wiii be absorbed differently than pump light pergendieolar to
`the Mtxis, Tizis wili _cause the pump disuébutitm (and thus the laser outgmt beam) to be;
`sfiiipticai,
`
`A
`
`" M ‘
`3.8"
`
`‘ 2.
`
`
`
`'
`
`-
`
`'
`_ 0.2 _
`“V
`‘g
`- M
`5 0.‘!
`V
`(LO?
`s=.
`§ 0.05
`» 3 0.64
`"§ 0.93
`‘O
`.
`:3 0.62 .
`
`’
`
`L
`
`.
`
`b
`Pink ruby
`ias-erred
`
`A
`
`’
`V 0.5
`Q 4
`*1
`Q3
`
`L5
`
`__
`NE
`to 0
`V
`$
`0.7 3
`3*
`,5
`2:.
`4?;
`§
`03 E
`035 «°
`’§~
`0,1 8<
`
`am
`
`.
`0.007
`
` 0.04 :’ V I I
`
`
`
`
`
`0.07
`0.05
`
`.6860
`6880
`6900
`6920
`6940
`6980
`6980
`7000
`7020.
`Waxieleragth A {3}
`
`Figure 11.3 Since ruby is nniaxia1,_ its absorption coefficient is a very strong function
`"of the polanization direction of the light,
`(From D. C. C_r0nemey&:r,» J, Opt. Soc. Am.
`5621.703 (1966). Reprinted with the permission. of the Optical Society of America.)
`
`‘
`
`

`
`Sec. 11.3
`
`Laser Materiais
`
`’
`
`351
`
`Btue
`
`1
`
`2
`
`4A
`2
`
`
`
`I
`
`1 Yellow
`
`Laser
`
`Vimonm Fjigure.