NLO Basics. Bulk Second Harmonic Generation Examples. QuartzQ ZnO bulk and nanowires Organic nanowires

Transcription

1 NLO Bascs Bul Scod Hamoc Gao xampls QuaQ ZO bul ad aows Ogac aows

2 Ahamoc Poals U U- P χ χ χ Io P lco pah P

3 Wav quao : quaos Maxwlls D J H B : chags f No 4 H B J D B μ ρ ρ s. : chags f No H H B J μ μ ρ : lao v Cosu P D D ε μ Cosuv lao : ad Us : lao v Cosu c P D ε μ ε v Cosuv lao coas dpdc m m dvg : quao Wav P P c μ v fqucy. ach fo quao O coas dpdc m m dvg P

4 Gal dscpo of ola polaao A g. ad pos. Ral! fqucy compos : Fld as sum of A Sam oao fo polaao : g. ad pos. Ral! P P suscpbly od od suscpbly. χ m j m m m j m P Sum - fqucy gao : dcs pad ov Summao χ χ χ j j j j j j P : SHG χ j j j j P

5 Ahamoc oscllao Quaum mchacs cssay bu classcal mchacs sll gvs a usful pcu U- Cosymmy UU U U U No-cosymmc UU U U... U du No - cosymc maal: F m ma d && γ & a c. c. m

6 Soluo of Soluo of ola quao h fom : λ λ λ Mus hold fo ay λ -o q.fo ms Is o dffal quao : λ : λ : && && γ & m γ & a λ : && γ & a λ o fo λ ms λ : Usual hamoc oscllao saoay soluo : j j D j j γ j m γ j j c. c. λ : Is - h - soluo saoay soluo : m a D D c. c.

7 Suscpbls P χ χ N md N N s ub of dpols p vol. P χ χ N χ N a m a χ m D D N Noc h fom of h scod od suscpbly: Popooal o la suscpbly! Mlls Rul : m a Thus N χ χ χ χ cosa cosa

8 P m χ j m Pmuao symmy j m m cs 6 dff sos 6 wh gav 7 lms ach 4 complx umbs Ral flds χ χ j m Pmuao symmy: χ χ j * m m j m m m Coacd oao : d ; ; j ; ½ χ j 4; symmy las wo dcs 5; 6 P d d d d4 d5 d6 P d d d d d d P d d d d4 d5 d6 Symmy pops wll duc h umb of o - o lms

9 Poblm Assum ha χ ad χ a compaabl f sma h scod od spg cosa ad dsac bw aoms l χ fa fom soac. Poblm. Boyd

10 Wav quao aga P D P ε μ wh P D c ε μ wh P P NL P c μ ε wh χ ε ε

11 Sum fqucy gao L χ Assum soopc mdum c c A.. : Soluo wh ε χ c c A c.. Wh ola polaao : ε c c A d c c P P.. Icd fld : 4.. da A P 4

12 Isd wav quao da A d da d A d 4 μ da A d : Slowly vayg vlop appoxmao SVA d d da d A d << da fom d od os od quao A A d d Δ Δ f ld f C d da μ A A d Δ flds pump Dcay of da Cospodg quaos fo pump flds μ A A d A A d Δ da pump flds Dcay of μ A A d

13 Low ffccy pocss cosa ad Assum A A A A A << ca b gad oly A A d d da Δ Δ μ ½ I L A I d L Δ Δ Δ ½ ½ Isy : L sc L A c I L Δ Δ ε ½ 8 L sc L I I d I Δ Δ ε μ ε

14 Δ P L Phas machg Dvg polaao ad gad fld has h sam phas vlocy I ₀ SHG : Δ o Uaxal cysals : oday ad xa-oday facv dcs KDP KTP BBO... θ c s θ cos θ o oday θ xaoday

15 Ma fgs θ Bag bw focd ad f mods

16 Spcal Ifomc scod-hamoc gao of fmo-scod pulss fom a qua wdg Thomas Bu Kss Kjld Pds ad Thomas Gam Pds Isu of Physcs Aalbog Uvsy AAU Dma

17 SHG wh sho pulss χ Th commg fld cas: Rflcd SHG puls Focd mod popagag wh h spd c/ F mod popagag wh h spd c/ Fo sho pulss h wo mods a spaally spaad a h x of h cysal M. Mlj.M. Wgh J.V. Moloy ad N. Blombg Phys. Rv. L

18 Dow covso pocss Rqus dlay l Puls boadg log KDP ffcs of goup vlocy dspso sho KDP Lmd o ~.5 ps L.D. Noodam H.J. Ba M.P. d Bo ad H.B. va Ld va d Huvll Op. L

19 Phas ssv dco K.J Vsa A.V. Phuov A.P. d Bo ad Th. Rasg Phys. Rv. B 58 R Masums of boh amplud ad phas of SH sgal Sampl: N Rfc: Pold polym flm Dspso glass: Δ ps

20 Tm doma : SH g :Slowly vayg vlop I Ω G Ω Phas ssv dco g g τ Φ Fou asfomao : g τ G Ω Ωτ [ α cosτ Ωτ Φ ] Ω :dvao fom c fqucy τ : fxd umb Ωτ : oscllaos wh pod π τ Auocolao : f ε ' ε ' d' Φ ε g g τ Cal pa ad wo sals a ±τ Ivs afomao whou cal pa Oscllag δiω c. c.

21 Phas masums K.J Vsa A.V. Phuov A.P. d Bo ad Th. Rasg Phys. Rv. B 58 R6 998.

22 S up

23 cgf Ma fgs

24 Dpdc o agl of cdc

25 Wavlgh hcss scas 6 Raw-daa xpms mm sca of Qua wdg hcss s [mm] Qua Wavlgh [m]

26

27 Dlay bw pulss No o dlay a pu fac!

28 SHG fom ogac aofbs Maula Schc Hos Gü Rubah Js Rafals Buldg blocs fo aoscal lcoopcs ola opcs hp://aofb.fys.sdu.d/dx.php

29 Asymmcally fucoald paa quaphyls

30 Fb gowh o mca

31 AFM scas CLHP4 x μm² MOCNP4 x μm² CNHP4 5x5 μm² <h²> Js Rafals

32 Roaoal dpdc Roao of pump bam polaao λ p 7 m I87*cos 4 φ. CNHP4 8 SHG ab. us 6 4 SHG I.6*cos 4 φ. Wll odd sysm Rspos domad by χ PL Roao Agl dg

33 SHG appas ogh wh ppl us 5 MOCLP4 λ 7 m Loa fs o phoo mods I sy ab. 5 SHG msso Wavlgh m Goud sa ad xcd sa o abov ach oh Absopo ad msso maxmum o a bad gap

34 xcao msso mssowavlgh plo h m Wavlg msso CNHP4 o Mca Nomald o qua log scal msso spcum codd fo ach pump wavlgh Pa of SHG mad 77 m Rpss h bad gap. Vcal l bod bw wo phoo ad h phoo lumscc Pump Wavlgh m

35 Compaso of h maals h m o Wavlg mss MOCLP4 Nomald o qua Pump Wavlgh m 5 msso Wavlg gh m MOCNP4 4 m o Mca Nomald o qua Pump Wavlgh m msso Wa avlgh m CNHP4 o Mca Nomald o qua log scal Pump Wavlgh m

36 SHG spca Isolao of SHG fom lumscc SHG lav o qua CNHP4 MOCNP4 x MOCLP4 x SH Phoo gy V

37 Absolu masums of χ MOCNP4 CNHP4 MOCLP4 Covag % 47 m o.5.5

38 SHG fom ZO aows Chsa Fs Fs Thomas Gam Pds Gowh fom ZO powd fuac a 7 9 C wh C as caalys

39 PL fom ZO aows Pump Bad gap PL xcd by m lgh: PL Sgal ZO ws o S/SO Dfcs Pa a bad gap 8 m G lumscc fom dfcs Wavlgh m

40 SHG ad PL fom ZO aows. us Is sy ab 5 b 4 7 m PL SHG m msso Wavlgh m mss o Wav vlgh m a SHG PL Pump Wavlgh m 5.. SHG Two phoo dfc PL Two phoo bad gap PL Th phoo bad gap gppl

41 msso fom dfcs ab. u s Lu msc cc Dfc msso λ p 75m λ 5 m τ 8s τ 86 s.8 y y A*xp-/τ A*xp-/τ Tm μs

42 Compaso of ws ad bul 6 SH HG I sy ab. u s 5 4 ZO ws o glass ZO cysal Ws hav maxmum wh h bul cysal hav mmum! Pump Wavlgh m

43 La opcal pops G.. Jllso ad L.A. Boa Phys. Rv. B Dlc c cosa a Room mpau oday _ _ c xaoday c Ral Imagay 4 5 Phoo gy [V]

44 Nola spos of aows I I d T T ff p p cosθ cosθ 4π L / λ cosθ cosθ 4π L / λ cosθ d ff Nomald spos 8 6 a ZO cysal ffcv mdum am of la 4 opcal pops: b ZO aows o S ZO faco % % % Pump Wavlgh m Ws ad bul cysal hav h sam ola spos

45 Cocluso SHG bascs Hgh ffccy a phas machg SHG SFG DFG OPO Pob of χ o cosymmc sysms