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Effects of substrate temperature on vacuum deposited thin film of disperse red 1 on ITO glass
H . T a u n a u n ' r a n g 1 ' 2 , H e r m a n 1 , a n d M . O . T j i a l
1 Deparlment of Physics, Institut Teknotogi Bandung, ialan Ganesa no.l O Bandung 401 32, Indonesia z Department of Phy'sics, L|niversitas Manado, Tondano, lndonesia
Abstract
Ilighly crystalline thin fllnr.s ol'photolefi-acrive l)ispur-sc Rcd 1 (DRl) nrolccule have been tb-bricated trn clean substlalc ol'lTo (indium tin <rxidc) glass by nreans of physical vapor deposition ut valious substratcs tcrnpemturcs. ln aciciition t<r moleculiu' odentation and olganization rcvcalecl by their XRI) ancl lrl'lR spcctml characteristics and the enhanccnrcnt of thosc etlbcts by substrale temperature, furthcr analysis of the I]IIR spcctrurn alouncl the nitrobcnzcnc absolption bancl inclicatcs the tbrmation o1' strong hyclrogen bond resultjng in a heacl-tail stacking of thc molecules" 'fhe
deposited lllms also show systcmatic recluction of light absorption in the visiblc region q,ith increasing subslt?lc tcnrpcratule.'lhis moclillcation ofthe optical proPcrty is cleiu'iy far,orirblc l n r l o n g w a v c l e n s l h p h o t o n i c a p p l i c a t i o n s o f D R I t i l n r .
Keywords : pltysitrtl vultrtr Lleposition; subiirale IetnpcrLttur(; tltitt iiltn; dtspersc rtd l; optical proparties.
Sari
Pcngaruh suhu substrat pada lihn lipis 'dispcrse rcd 1' yang didcposisi pada gclas ITO dalam vakum
l)alam eksperimen rni Lclah trcrtrasil clipeloleh nrclalui proses dcposisi vakunr scjunrlah lilm tipis bahan lotorcll'aktif dali niolekul
"Dispelsc Rcd 1" (I)Rl) dengan kr-istalinitas tinggi cli atas substrat gclas ITO ("inciiurn tin oxiclc") pacla berbagai suhu. Selain clek orientasi dan organisasi molekul yang ditunjukkrn oleh karakteristik spcktra XRD dan F-flR bersangkulan serta peningkatan et'ek
t e r s e b u t c l c n g r r n s u h u s u b s t r a l . a n a l i s i s l c h i h l a r r j u t d a L i d a t a F T I R d i s c k i t a r p i t a a b s o r p s i n i t r o b e n z c n a t e J a h m e n g u n g k a p k a r r ta n d a p c m b e n l u k a n i k a t a n h i d r o g e n ,var)g kuat yang rnenghasilkarr susur)an "hcaci-tail" yang bcrtumpuk. Irilnr 1,ang ter-deposisi j u g a n r e m p e l l i h a t k a n l)engurangart absorpsi cahaya sccala sistenratik di claerah tamprk, seiring clengern peningkatan suhLr substrut.
P e r u b a h a n s i t i r t o p t i k i n i j e l a s b c l m r n l a a t b a g i a p l i k a s i t j l m D R I u u l u k r l c v a i s lb t o n i k c l a l a m d a e r a h g c l o m b u n g p a n ja n g . Kala kunci : deposisi vukurn; "disl.terse red l";J'iltn tipis; siJht optik suhu sribstrut.
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1 Introduction
O p t i c a l n o n l i n i c a r ( O N L ) o r g a n i c m o l c c u l c s c o n s i s i t i n g of corrjugated chain and elcctron donor as well as electron accel)tor groups such as DANS, MOlrS. DO3 and DRl. have bcen studied tor thcir photorcl'ractive and second order optical nonlirrear prol)crties which arc uselll ibr t variety of applicatior)s such as electrooptic ru)odulation. optical switching, Iiequency doubling, and optical data storage [-7]. For those photonic dnicc applications. the ONL orgarric lnaterials arc gcncrally required to bc preparcd in the tbnn of good cluality thin tlhn, charactcriz.cd by its good optical transparancy, thickness trornogeneity and surf'ace snroothness in addition to its appropriatc nonlinear optical propcrtics.
The physical vacuurn deposition (PVD) rnethod has bccn dcrnonslrated recently as a viablc altcrnativc for organic lhin fllrn fabrication, spccifically frrr lorv rnolccular weight chrornophores rnolecules such as p-NA [81.
D M A N S [ 9 ] a n d D i s p c r s c R c d I 1 1 0 . ll l . I n a d d i t i o n t o
producing filrn with high purity and hornogencity. this rnethod has also proved to bc cfl'cctivc irr prornoting rnolccular oricn{"ation in thc filrn lll lll. This etfect is cxpected to inducc changes in thc tlhn's optical propcrty.
ancl with lirrlhcr arrangement ol- thc oricntcd rnolecules.
rvill rnost iikcly lead to consideral>le cnhancernent of ils photorelractive and nonlinear optical properties.
lrr our previous rcport on the rcsult o1'physical vacuurll d c p o s i t i o n o f D R I l l h n o n s l i d e g l a s s e s [ 1 0 , l 1 ] , t h c nlolecules in Ihc lllm were shown to be organizcd and oriented pcrpcnclicular to the fihn sur{accs. In this expcrirncl)1, thc PVD melhod was clnploycd for the l)reparation o1'Dispcrsc Red I (DRl) thin fihn on i'IO glass substrate at substrate telnperatures in the sarne railgc of variation. Thc dil'f-crcnt substrale telnperatures rvill bc shown to induce changcs in thc optical lbsorption charactcristic of lhc rcsultcd filnrs. This result rvill bc cornparcd rvitlt our previrtus resrrlt on DR I thin (llrn vacuurn dcposited on slide glms substratc I I I l.
26
2 Experimentdl 2.1 N'Iatcrial
Porvdcr of' Dispcrse R.cd I (..l-ll'l cthi:l-N-12- hydroxycthyl)larniiro-4'-nitrorizobcnzcnc ) was obt{liiled cornrrtcrcialll, iiorn Sigrui. Tltis niolcrrulc has a [irrrrnila weight ol' 3l-1.3. and thc rnclsured vahies ol rnclting point and thc ()nscl tcrnpcrltirre of thcrural d e c o r r l r o s i t i r ' r t a r c 1 5 3 ' ' C a n d 2 1 9 " C . rc s p c c t i v c l l , I l l l . Thc stnrcturc of' thc rnolccrrle is shorvn in Figure (l).
This poldcr ivas usctl lbr i,acuurrr cieposition rvitltr-lut lirrthcr trcatrncnt. As sccn llrrni thc tigurc, thrs rrutlccule c o n s i s t s o l ' l N - c l h y l - N - ? . e t h y i h 1 , c l n r x 1 , l a r L r i n o a s t h e electron donur groull. lintl hlOl as thc elcctron acccptor groups, with thc conjirgrtcrJ-chain azobcnzerlc scrvrlg rs the n-electron bridtc bctwccrr thc two groups.
I'itoc. I'f iJ. | {)t.. 3i, No. t.2001
lihns gi:ite n;ii;. exhilrit srnootir surfacc and hurnogcncous [hir-:liiicss.
Thc icsuit ot' FIIi{ rnellllrcrlreoI prcscntc(l in Fig. (2) consists of sllL:ctrtirn oi thc (lr) pristinc DP. I porvdcr, (b) D R I lnrvdcr obtaintd by pulverizing t h c I r h n d c p o s i t c d at substratc lclnpcranrre of' 26'C, arrtl thut of (c) the dcpo:,ited Illrn. It is otrscrverl that thcre is no rncaninglirl difl'crcncc bctrvcen sllcctnnlr (a) lrrd (b). irnplying no s i g n i l r c a n t s t r u c t u r a l c h a n g e d u e t o t h c d c p o s i t i o n pfoccss. Mcanrvhilc" thc prcscr)cc of rncllecular oricntation ct't'cct is clcarly indicutctl by cornparison of ( a ) r i i t h ( c ) i r s d i s c r : s s c d i r r d c t i r i l in o r i r c a r l i e r rv o r k
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F i g u r e 1 M o l e c u l : i i s t r r c i u i * o f D R 1 [12]
2.2 Samplc prcparal.irur
D i s p c r s c R c d I t l r i n t i l i i r w l r s 1;rcparcii i r : i . ' l ' ; - : l l i ) Vacurrrn Evaltr;riitor lrorn Lh,ac lJinl<;r Kiko, rvlricl: rvas opcratcd at about 3 r lt)-5 Torr. Thc Dirpersc Rcrl I (DRl) thin filnrs rvcrc dcpclsitctl on clcan niicroscopc slides glass. and Il'O glass. For tlic dcposition pfoccs:ic:i t h c s e s u h s t n t t c s w c r c p l a c c d : i t a b o r r t 1 0 c r t i a b o v c . t h c cnrcitrle. Follo*ring orrr prcvi<urs exlrcrirnel)tal resuli on the optimal cvaporatioil tcrnpcralure lilr the <Icpositiorr proccss [1] I. thc cruciblc tcu)l)cr'a(urc was sct at 173''C in this cxpcrinrent, w'hilc thc sctting ol' substratc tcrnl)cratufe wls inorc or jcss cqually spaccd at 26"C, -55"C and 75"C Abr,vc .1-5''C. tho deyrusition latc drrrltped drastically drrc to rc-cv.ip()r ation cl'fcct. No lirrthcr annealrng trcaturcni rvas corrilucted on ihc ils-grown 1llms.
2,3 Characlcriz:rtiun
T ' h c c q , , s t a l l i n i t y a n d . r r y s l a l i , t l r r c i i r i e v " e i c c x a r n i n c d o n thc hasis ol' XRD llcttcnls otr(;incd t') Plrilips Difiracturnetcr r';hich was olturateri rvith the CirKc, 1A =
1 . 5 4 0 6 A n g s t r o r n ) X - R a y s o r l r c c . T l r c o p t i c a l rneasurcrlrenl tlf thc pristirrc l)oijicrvritallil': ltorvdcr and vacuuln dcpositctl DRI thin l'ilin ivcre charactcnzcd by a B c c k r n a n D L I - 7 0 ( X ) S i n g l c B c l n r S p c c l r r l l i h o t o r n i t c r . The thickrrcss ol'thc lihn r',,as dctcnnirrcd bv Dektak ilA depth profiler.
3 Resuits nnd discussions
The ntcasurccl tlrit:hncss rif thc ur apt)rate (l I-rlrrr ,'trrics liorn 0.3 to 0.7 prn lor ilillcrc-:rt lilrns. Tlic dcltosilcd
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Figurc (3) slro*s thc rcslrlts of XRD rncirsrircrncnl lirr thirr ll iin as tlc;rositcil tin ITO gllrss tt substratc tcrnpcr0turr.js of 26''C (a), .5-5"C ib). and 75"C (c), rcspcclirrely. T'lris [igurc w'as rrornralir;ed lcl thc llhrr's t h i c k n c s s . T h c X R D r a ( t c r n o l ' I l - O g l a s s ( r v i t h o u t D R I llirn) is ulso prcscnied rtlong irt lhis fisrrrc fbr colnpunson aild pr0per il){erprcti.ltion o[' lhc spcclra. 'Ilre
dif'frac:tion pcak-al 20 = 9'' corrcsponds tri intcrlayer tlistance (d) o{' 9.13 A which isr not ltr l'rrtrn lhc lcngllr ol'az-ol)cn/-el)c ill t h c t r a n s - i s o n r c t o [ - D R I ( - 9 A ) tl3] .rugucsting t h a t DR I rnolccrrlcs iuc oricritcd pcr'ltcndicular to the substralc's srirfacc in a Iicad-tail c0nl-iguration as s u g g s s t c d i n r r u r p r c v i o u s w o r k l 1 l l . T h e p e a k a t 2 0 = 30" originatcd lirtrn (hc ITO glrss rcrnlrius rnore or less constalrI with rcspcct io the glirss tculpcratufc. While thc p c a k i n t c n s i i , T a s s o c i a t c d w i t h D R I t h i n f i l r n t i o e s n o t
PROC. ITB, \/0L. -t-J, NO. t, 2001
seem to undergo any visiblc change, but the siti:(rtiirl width does display visible reduction with increiislrg substratc tcrnpcrature as obscrvcd in Fig. 3(b). (c) tnd (d). This systematic changc of the XRD spcctrurri indicates an irnproved crystallinity (crystallilre nroleculiir' organization) in the flhn with incrcasing substrllc telnDeralurc.
rr{- -**--3*. +-i-d*-/r.-**i *,-,.,.,.-.
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Figure 3 XRD patierns of (a). ITO glass without DR1 filrir, ri:) Disperse Red 1 lhin film deposited on ITO glass at 26"C (c) 55"C, (d). 75"C.
Irt connection with thc suggested hoad-tail stackirl$ r);
those rnolecules it is usclul to take a closer look at Fr6.
(2), sllccifically around thc nitrobenzene band ai 13,-$
crn-' , rvhich has been scalcd up in Fig. (.1) for a cliise-ul) vierv. Evcn a cursory view on those spectral brrrcls wrll lead to a confirrnaticlrr ol thc lorrnation of the heati-larl configuration via the strong hydrogcn boncling o[ thc type O-H O betleen thc ni(ro group of the accsl)tor arri-l the hydroxyl group in the donor as depicted in F'ig. ("i) urd cxplained in thc lirllowing. We note l'irst ol'rll :i visible rcduction of the 1340 crn-' :rbsorption band going from (a) to (b), rvith the appeararrcc of a sura.ll kink to iis right (locatcd approxirnately cr 1330 cm-'). lt is ro bc cxpcctcd on gcneral ground lhat the litrrnation ol hydrogen bonding tvill suyrpress the abovc lncntioiicrl absorption band. Howevcr. thc suppression is less thlir cornplete sincc a goocl part of thcsc borrds rvere alread';
disnrpted by the proccss of prrlverization. Thc prcscncc of the rcrriaining bonds responsiblc for the reduction of the 1340 crn-' band is also conflnucd by the appoarancc of' thc srnall kink to its right as alludcd above. 'flii:;
interprctation is further cvidcrrced by thc rtcar tlisappcarence of thc 13.10 cnt-r bantl alorrg with thr strong enhancclncnt oi the 1329 crn-r band showil iri trig.:l (c) which is associated rvith the eficut oi hl,drrrgeir bonding induced by the deposition process. It is rvi:ll knorvn that the lonnation of hydrogen bonding I 1.ll w,ill gcnerally lead to a down shil't o1 the absorption bart(l along with its broadenirrg, irr confonnity u'ith {lrc obscrvation described above. lt is further noted that thc cnhancecl intensity ol'lhe 1329 crn-rband is still short ol"
that ol' thc original l3-10 crn't band since the rligitcrl rnoleculcs arc cxpected to supprcss the coniribution corning lirrrn the vibration rnodc aloirg the long rnrrlecular iuiis.
\\'ir,,'i: Ioiuttt bcr (ctn'l)
;:rr.!c rlp ,,icw cf FTIR speclra around the nitro I r'i!r liai]cj lor samples of (a) pristine powder (b) zir.i fiurn deposiled film. and (c) film as deposiled
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:: rf hydrogen bonding between lhe nilro group ii:.:,rrp ui lwo DR1 molecules as suggesled by ) 1
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* ' i t h i r * , r r v c l c n g t h o l r r n x i n u r n r a b s o r p t i r l n l o c a t c d a t .i()fi rrrn (4,.,.,.--5111i nrll). 'l-llis
broad absorlltiorr band in
\ / l S - r c ! r r l r i ( . i 0 6 r ) r l i l s c t l r t t r . n o r r l y a t t f i b u t c d t o i n l r l r n o l c c u l a r c h a r g c l r i u l s l ' c r ( C T ) t r a r t s i t i o n o l ' t r - c l c c t r o r ) lr o r r r t l o n o r ( N - c t h y l - 2 N - c t h v l h y d r o x v l ) t o iicccl)l()r sr()U[) t NOl ) r,ilr lhc corrjugatcd-chirin I r z o l ' r c n z c r r c l l - 5 1 . T h c i d c n t i c a l a p p c a r a n c c o 1 ' th e t r v o l r l r s u r p t i o l r h l t r r t l s i r r t h i s r c g i o r r ir t t p l i c s th a t t h c r r n a l r l c p o s r t i o n p r o c c s s t l r t l r r o t c a u s e a n y c h a n g c ir t t l t c c o n j u r a t c d s t n l c t u r c o t ' D R I r n o l c c u l c . T h c s l i g h t s h i t t o l ' t l r c p c a k t ( u c t l ) c r u ' i l h t l r c c o n s i d c r a b l c s u p p r c s s i o n o f l l r c L I V h u r r d o l ' t h c p u l v c r r z c d l i h n r n a y a l s o b c r c l a t c r l r o i l r c p r c r c r r c c o l ' t h c r - c r n a i n i r r g h c a d - t a i l h - v d r o g c r r l r o n t l s i r r t h c s l t r r r l t l c . H o r . r ' c v c L . t h c t l c t a i l c d c x p l a n a t i o n ( ) i tl ) c c l l l l r l r c s r c c l u i r e s l i r r t l r c r c x l r c r i r n c n t a l s t u d r .
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Figrlre 6 UV.VIS spectra fc-r, (A) solution of Ulsperse He,l i pr stine powder in NN4P (B) sotution of Disperse Red 1 powder pulveflzed trom fiim deposiled at 26'C.
l ' l r c c l l i t t o l s r i l r s l r l l t c tc r r l r e ' r ' i i t u r c { } r l t l t r : L I V - \ ' 1 5 , r i , s o r p t i r t r r 5 l ) c c t r i i r ; l t l t r r ; l l l r r r s ( i c p o s i t c d o i i l f O s l 0 s s u l I o ( ' . - i - i " t ' i r r r d 7 5 ( l r s t t s s c r i l l e r t i n F i g . 7 . lI r s t : l c a r tl r a t r r c , " r lc l r t L r r ' c s a l r l l c l r i r i l l l e s c s l l c c t f i i . B u t i i r n o s t r e r r r l r r k l l r l c c l ' l ' c c t i r ) t h ' s s l ) c c l r a i s t h c p r o r r 0 r r r r c c r l r c t l r r c t i o r r o l t l t c I o r r r . r v i r v c l c r r g t l t i v i s i b l c l l i b s o r p t i r t n ' l r l r r r t l . I i r r : , c t l c c t i s c r r r r s i r l c r a h l y l t i r g c r t h a n t h a t i r l r : c l r c t l i r r l h c l l l r r r \ . l c u u r l t r l o i r o s i t c d o r r s l i d c g l a s s l l l l l t r \ e c r l i r i r i l v i r \ \ ' c l L o r r i c c h a n g c la v o r a h l c l i l r t h c r l c r il o y r r t r c r r t r ) 1 . l o r r c r ' , i t v c l c r t g t h a i l p l i c a t i r t r r s o l ' l ) l ) ( ) t , ) n i r d c r r i u . A r r t ' l l t c r ir r t c r r s t i n g c l x i n g c i r r d u c c d [t y ' i l r c r l e p o s i l i o i r l l r ( ) r c s s l r t l t i g h c r s u b s t r a t c t c n r p c r i l t u r c i s l l r e i r l ) J ) c a r i l r i c c i t r ) d c t ) l r i t l r c c l l t c r l l o l a D c r v [ I t n t l a t t h c j o c i r l ii-r(1' lr.rrr:itiorr ()l tritrls itzol)cr)lcrlc I I f,l. ir n r t l l c c u l l r r c o r r l l s r r l r t i o n ll i r o r c d i l t h i g h c r t c n l p c r a t u r c . F r g . 7 a l s r l d i s l l k r r , s l n i n t r i u u i r r g c l l b c t r n a n i l c s t c ( l i l ) t h c c r r h i i r r c c r r r c n t t i l ' t l r c L i V a b s o r p t i t i n b a n d . i l s s p l i t
\ t n r e t u r c lu t c l a r . c l i r l i r c i n t c r ) s i t y s h i l i i n l a v o r ' u f i t s l o n e r r , , r l v c l c n g t l ) c o r r l ) ( ) n r ) r i t . W c r x ) t c th a t ( [ l t l i t a t i v c l y
I ' R 0 ( - I ' I ' B \ / O L . . 1 . 1 , N O . 1 , 2 0 0 1
l L L l 4 U U ! : _ l L l r i j u i [ - 8 0 0 l"/Li'r'1 iritJll't it)ri )
Figure / UV-VlS speclra of Disperse Red 1 thin films as deposited on ITO glass subslrale at (B') 26"C (8") 55"C (8"') 75"C. indicating modification of oplical propenies induced by elevaled subslrate temperalure.
sirnilu' chnractcristic changcs due to higher substratc tcurpsraturc rvcrc also obscrvcd in filrn deposited on s l i d c g l a s s a s s h o r v n i n F i g . t t [ 1 1 ] l' o r c o r n p a r i s o n . I t l n r r s t bc strcsscd lrt)wcvcr, thllt thc changcs obscrvcd in the two cilscs dil'l'cr in dctail as well as quantitativcly. A consistcnt cxplauatiorr {irr thc two cascs is unfilrtunatcly not availablc lrorn this cxpcrirncntal rcsult.
I i
1 l l 0 - r l
! j l - t - ; t - r '
. i . . r , 1 ' l - r
- l r l u , l L , r
I r ' lr : 1 1
l j t | - j i , ; - ,
l L i i . l 1 t l . ) t - ) :J0 L i a r j 7 I'J l l 0 r . )
Wavelength (nm)
F i g u r e 8 . U l - V l S s p e c l r a o l D i s p e r s e R e d 1 t h i n f i l m a s deposited on glass subslrale at (B') 26"C (8") 55"C (8"') 75"C
4 C o n c l u s i o m
It hts beerr tlcuionstratcd irr this cxperilncnt that hurnogclicous thin I'ilrn ol' DR 1 coukl bc vacuum d c p o s i t c d o n I I O s u b s t r a t s . l t w a s s h o l n t h a t th e f i l m cxhibits sirnilu spcc:troscoltic l'catures indicating r.rullccular oricrrtution anrl organization cffccts as shown by thc filrns clcpositcd prcviously on a sliric glass srrbstlatc. Wc irrther substantiatcd thc proposcd head-tail r n o l c c u l a r s t a u k i n g o r g a r ) i z a t i o n b v i n d i c a t i n g t h c r o l e o f
!-:
f_:
Lr 5.r,i i.l U i ' t l r I i l 5 2 t ' I 0 ' 1 6 t -
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1 1 .
i i
c)
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I'R(.)(',. n-8, \/OL. 33, NO. L 2001
hydrogen bonding frorn thc FTIR data. Among thc most rernarkable ell'ect obscrvcd in this experiment in the long wavelength absorption reduction at elcvatcd susbtrate telnperature, which prorniscd lirrther developrnent of DRI film for photonic devicc applications.
5 Acknowledgments
Wc thank Mr. Arninudin Sulaernan lbr hclp with FTIR and UV-VlS lr)casurcrncnls.
6 References
l. Prasad, PN, Orczyk. ME. & Zicl't't. I, Pollrneric' C'ontpttsite Material.s .for Nonl.inear Optics afid Phcttonir:, Nonlinear Optic,s,14, pp 121 -l}t, i995.
2. Kaino, T, Yakoo, A. Asabe, M. Tornaru, S, &
Kurihara, T. Organic Nonlittear Optical Malerial,s for Device Applications, Nonl.inear Optic',s, 14, pp.
1 3 5 - 1 - s 0 . 1 9 9 5 .
3. Mohhnann, GR. Developrnent of Optically Nonlinear Polyruers and Devices. Synthetic Metals, 37.201-221. 1990.
1. Hu. S, Carlislc. GO, & Martinez, DR. Absorption Studics of polyrner d_ye fihn orien(cd by corona poling. Journal of Material,s Science Letter. 17,991- 7 9 6 . 1 9 9 2 .
5. Sotyarna, W, Tatsur:ra, S, Motoyoshi, K, &
Yoshirnura, T. Dircctional-Coupled Opticll Srvitch Betrveen Stacked Waveguidc Laycrs Using Electro- O p t i c P o l y r n e r . l p n . l . A p p l . . P h t . s . . 3 1 . 1 1 u 0 - 1 1 U 1 .
1992.
6. Shishido. A. Tsutsrrrni. O. Kanaz.arva. A, Shiono. T.
lkeda. T, & Tarnai, N. Rapid Optical Switching by Means of Photoinduced Change in Relractivc Index of Azobcnzcnc Liquid Crystals Detcctecl by Retlcction-Mode Analysis, J. An. Chent. Sor:., ll9, 7 1 9 t - 1 1 9 6 . 1 9 9 1 .
1. Nlcng. X, Natanshon, A. Ba-rrctt. C, ct Rochon. P, Azo Polyrncrs for Rcvcrsible Optical Storagc. 10.
29
Cooperativc Motion of Polur Sidc Groups in Arnorphous Polyrners, MacronrolecuLes., 29, 916- 9 5 2 . 1 9 9 6 .
Okarnoto, N, Unoh, H, Sugihara. O. & Matsushirna, R, Largc Sccond-Harrnortic Generation irt Cornposite Fihn ol'p-Nitroanilin antl Its Derivatives, Nonlinear Optic,t., 14. 245-250. 1 995.
Ehara, T, Hirose. H, Kobayashi. H, Kotani. l\'1, Molccular alignrnent in organic thirt llhns, ,\vntltctic M e tal.s. 109. 43-'16, 2000.
l'aunarrrnang, H, Herrnan. Tjia MO. ['reparatiort o.f Disperse ReJ I '|-hilt
L-ilnt by Vac'uutt Ev,aporation Method, Prosiding Sirnposiunt Fisika Nasiottal XVllI. Scrportg, -l(r-5-472. 20(X).
Taunaunrang. H. Helrnart. Tjia. MO, Moleculur Orientation in Disper:;e Red | 'l'hirt
l'-iln I'rodrrtatl bv PVD Nlethod, subsrnittcd to Optical Material.
Singor, KD. Sohn, JE, & Lalarna, SJ. Scctrnd harrnonic generation in poled polymer lilrns. Appl.
P l n ' s . L e t t . . 4 9 . ( 5 ) . l ( ) E 6 .
Nuykcn, O, Schcrer, C, Bairrdl, A, Brcnncr. AR.
Dahn, U, Gartncr, R, Kaiscr, S, Nlatusche, P. &
Voit, B, Az.o-Group-Containing Polyrncrs lilr Usc in Cornrnirnicatiort Tcchnologics. Prr.rg. I'ohtm. .\ti., 22. 93-183. 1991.
Colthrp. NB" Daly, t-H, Wibcrly, SE, Introdrx'trtttt to Infrared antl RanrarL ,\pc(tt o,tcopy. Acaileutic Press. Lonckrrr. 1975.
Sotoyarna, W, latsuura. S, & Yoshira, l', Electro' optic Sidc-Chain Polyirnidc Systcrn with Largc O p t i c a l N o n l i n c a r i t y a n d H i g h T l t c n n a l S t a b i l i t y . A p p l . I ' l t v . L a t t . , 6 4 . ( 1 7 ) . 1 9 9 1
A s t r a n d , P - O , R a r n a n u j a r n , P S . H v i l s t e d . S , B a k , KL. & Siirrer. SPA. Ab Initio Calculation ol' tltc Electronic Spectrunr of Azobcrrzertc Dyes anil lts hnpact on tlle Design ol' Ollticlil Data Storage lvlrtcrials. J. Artt. ('lten..Sor'..122. -l-{t'i2 3.{1i7, 2(n0.
u.
a
l 0
I l .
t 2 .
1 3 .
t 4 .
1 5 .
