V, LJ ii a:
Heitlep lonacu caung ta co nam scng eua xax ezzc:zzcn nn\ sau /±iE/
sau /±iE/ i = : LMi+^iftrji"^ y '6 .<- G./^^tu)-.;^uy ^ . y (5-3-1) 4>.= A-- 4 .r i ^
86
^ 3 - 5 - 2 ) , / ' , , 7^ . F.- ; - h
- ; i - - ^ -^ ~ - je
l a t x c h phan t r s o d o i .
àp dT^ng ( 3 - 3 - 1 ) va ( 3 - 3 - 2 ) vào ( 3 - 2 - c ) , chung t a t h u
-.^..t. -^-a ^--^ oua z v^; v^ g ',ay nau s a u :
0 • c f. ^"i i - ^ t ^H ' "F r o ' i f^ 4- \ i / ^- I - r-;^\ I . : T ~ " - F X í-x ^ •\3-:>-:) '• •• « i K ; • ^ • - ^ q (f ) r K G H ! y ~ ~ - x i n j ' y —> \
trong do 1 :T'; va :-Î f'"f ) là anh xourier cua j-i^ I va '^"i^) • Nhçn thay ring, khi chung ta cho S(G) - 0 d (5-5-5)/ ehùng ta de dàng tlvx Ici d~dçc cac ket qua ban
1. r - ^ - - - : > • r
S';
•4. G = H?. 5:7 0 153 n£,>,3j
_ ^ _ — V
vt'—p ^>
K ; / ) - '•-""•h\
Ohunz^ ta nhçn thay rang de co hiçu t^ng trao doi d hç 30 chuan hoa hàm song cua hai exciton, tUdng tac thâng giùa hai exciton là khac khong va trd nên quan trçng trong
tr^-^dng hijp t;idng tac day giùa hai exciton. Gia tr^ tuyçt do:
cùa yàu to ma trçn trong trtiâng hdp tudng tac ' 'dáý ' va
- 5<:
cua <l^^^)j i5n zh dSi già tri eÙ3 ji^^WJ
Ge kiem nghiçm Ici ket qua vùa i:hu dudc caung ta ^ne su aung se ixçu thitc nghiçm cua tadng tac hsi nguye: ta hydrogen d trçng thai co ban /II9/ de so c
7 ^
••J" J- d o . nang -i-U^ng tudng t a c aay va t a d n g t a c xut c^
•ai nrzuz^ên t ù hydrogen l à ;
h'
^)^,y = - ••' ^'G' ^H'
^ ^ - > — ^ y
trong do E ^ , •§ ^ la nang lu^ng ion hoa va ban kinhijohr
' • ii h ' ' ' ' 0
eus nguyen tu nydrogen. Aet aua la xna phu hcip xçc oxet aox vdi trUdng hçp tUcng tac *'daý*.
IGnti vçy, neu xet tadng tac exciton-exciton d erudng h^p spin cua hai diçn td cung chieu, nghxa là truông h^p t'đng tac ''daý' thx hiçu dn^ trao dei d h§ so chuan ho p
hàm song trd nen quan trçng va cho dong gop con khi xét tttdng tac exciton-exciton d trttông h^p spin cûa hai dien tG khac chieu nghxa la trudng hçip tiidng tac ^ ^hut^ ^ thx co the bo Qua hieu "dng trao doi d hç so chuan hoa hami song cua
e;^ -
- •; • e-...ex u Ga-"P e ^ ^ r x - e n ^ x e n g enạ- zan x a n - a>.j.ung t o •-» ~- u iH'^t so X-- J -Lù^n nnủ s a u :
Ụ..ỊSC 1^
- :Ji^a r a *av.^c ..y : x u y i t axnn pno e x c x t e x - p o m a r x t e n
exa ^an -an G^p _"nuyng»
- I x n u axQ'c ^^o e r i . e a a I^^G dao d^ni2 d l j u xea c x a
j - t o n X—ç -• Oan x a n . . "; .•,-. .xruc vung i:.,/ J - ^ X . A i t a x a p a n
••z-~- ' J'"^.'•' X'• uC r'-' ~^ '••-'0 1. "•'''^ jX'^'^''^ x j '."••-r- ^ " n n ,_>_-•••-' a ' j
^an s:-c e:^a ; : a l a r x t e a G znhx» b a a d a n b â t dzz^nz xiG:"ng ehc
• ' - — -, - , ^ ' / • —
-„ .-. . -x ',.« - •-, " "• ' T r ' ' ^ • " • •"''"T " ' " - ; f i • • ' ' •
- - , . . . - ._:;.* -.— _* • - - i ^ ' - ^ - — - - ; — ^ - . i - ^_ ^^ ^- - ---ji-i -.----rLị ' - t-- - ._ «
—^*3»
_ > . * * - , " • , - . ^
- pc-axxtoa tx Iç qua ýiu te ma ^rçn z^zon^ tac excxton exciton nhân tham oàc tnii/o eo ^ai chuan hca va cac '2:à-az 36 vectea ^^^'^z^ thày rang khi txnh yiu tt ma trçn exang tac
exciton-exciton, eac thài kê den hiiu ùng trao doi c hç
so jxuan n.:a ham z.onzt eua aax sxexton vx l:^c
"" " " an Iv'o txóag tac hut cùa chung.
Ss^ xoag gop cua .oxsu ung trao aox c n^ -^n -^:- • song càa hai exeitca là :aan trçxg.
- -rùL ys ^ ys ^ x a c . d o . : . VJ —, / _ •^ n::n:i ^ Ç t xy .ly t n u y e t • ïiruox, ^ a n t a u mudx mçt <J Cl i l -t k ^ O •-> n x n , ^ a n unu -•1 T- / I / ' K. ^^nan x x , x g u y e n xx v x e t t ç p cnx v ç t xy C / 2 / K. Chan d y , Nguyen , i i y i e i : C z e c n o s x o v s x . o . p n y s 1966 d a n g i n .
/ ^v •ru^en v.:iii hX2.u ^^1 V i e t aạ aạ
-jz -
T, r
^.-=> 6^" -<^—^ ^s.]/ oc xong exet dn sau sac vex ngue;
tnsy cua minh la Vien sx xguyen Tan Miêụ Vien sx luon
lucn quan tam tdi vice dào tço eàc tịï hç Iznoa hçc tra
Vdi niem mong Udc iSn nhat 1 ta u ruyen tnç. aUdc net cae xxen
thitc va kinh nghiçm nghiên cùu cùa ban thân cho eàc nhà khoa hçc tre, trcng do co tac giạ
vdi td cach la ngi^oi thaỵ Vi^n sx xa ixicn Ixen ehec
aoi giup đ truyen l^i cho tac xia eàc cSnx eu v:^ xhiUdna pnap as gxax quyet nhung van ae eçi txẹ esc xe tax trxnn
"1 T- -n
J 1.1'S.IL:.^
bay trong luçn an do Vien si de XUST; da dudc hoa
dudi su hudng dan tçn txnh cua Viçn ex.
lac gia rat may m^;.n đc^c làm viçc tçi truxeg tax vçt
dy ly tnuyet aay txnn tnUcng yeu aong enx va eran zziz^c
khong khi saj me khoa hçc dị"di sU Isnh dço cua giao su
3ào Vçng BÙc. lac gia xin chan thành cam dn giao su i)ào Vçng BÙc da luon luon quan tomi theo doi, giupđ' chx bao,
khuvsn khxch tac gi *> , ^ ' , > 1 ^ •
1,^ ^—. -*.—. _w^- rj— jr0--g suou qaa ^j___iii,i j_jui
lâçn an. lac già xin chan thanh cam on thày Nguyen ii
Viçt trong suot qua trînh làm luçn an da luon luon giup de nang caa trînh dg hieu biet ve cnuyen mon cho tac gia va da dong gop vào nçi dung de hoan thành ban luçn an nav.
lac gia :-xin cam dn cac áong cnx -nguyen xoan xnang, aa 'Iịnn
cn:^ em cac eçn treng Irung tam vçt xy ly thuyet dl quan '^am :gxup ad tac giạ
loC gia xin chan thành cam &n ban giàm hieu nhà tr^adng cung nhu khoa nang cao trxnh dç IrUdng 1/çi hçc tong h^p
ha nçi da tço mçi dieu kiçn thuçn Içîi cho viec hoan thanh ban Luçn an naỵ lac gia cung xin cam dn cac thay, cac cô d khoa 7çt ly cùng nhu d to bç mon Vçt ly ly thuyet cua trudng da euan tam theo dei dçng viên khuyen khxch tac giạ
. . . - . - . , J
^ung xxn cam en cac ann, cac cn^ cac c^n d to may txnn tnuçc
viçn ky thuyçt diçn* tu da giup do va tço dieu kiçn cho tac ^ ^ia sú diçng may txnh gop phan hcan thành luçn an naỵ
La mçt nznz^en cuu -32,nn nudc Oçng noa dan cnu nxan aan ịac dUç'c làm viçc dudi su hUdng dJn cua Viçn sx Kg'uyen Van Z-îiçu,
mçt zzihà bac hçc cà uy tin, mçt nhâ su phçm day kinh n;5uiçm ,
do là mçt niem vinh dy Idn doi vdi tac giạ Tac gia thay can phai hçc hoi hdn nùa, không chx hôm. nay ma mai mai de xung dang là hçc trô cua Viçn sx
à3 -
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n u^^ôin-Pûiri*:.^^ C.Ẹcurtiss, R.B.Blrd, Molecularnaia
X. . f
De txnh y^u t5 m^a tr:ai
ç i •'- ".V?^ ii^l = ^^r%.-^^\))
cnung ta txnh veu te ma trân
ou aung axnn >^_.ị_lc-^- U-i)(V|X'''i\=^-l)'"" L -V, '' •! e\ -Th 1 m (VllIllU) e é 2 ^ (^'Rx=Hx« . .iZ^^x,^.^n
Su dung txnh chat 3j, chung ta co
\ * . e - ^ , i ^ e ) = i î ^ | r [ l ^ _ ^ ^ j . : ^ . (A-2) (A-2) \<e-iif,il\ô I/X ;/!i^f^ii£dt2; ^ 1/3 1 ;/ (l[(ịZ ^ *' iJiT^ Z/<^}
C u o i c ù n s Caung t a t a u du<^c:
^ \ . , • -^^%) fioK^^e)
CA-5)
^^ée-x4'^l)^-/-'"^1
, ,, ^'«^ -? '• v% '
rn - • i 3 don;^ gop eu:
:rong cio J L f, • ^- ^. - ^ . - c a c p h a n g o c : U i . U i J - o CtT) '^V - ^, ;«-w;(etTv,)i
(A-4) ;îe-tj^iïe+4jiie-5) .^^i^<^jli^-<))U^-t-»^^-j)'(ẹ-m-<^)! J
V(,l^<l^ịli^-H.:*ll!;^
- î r l -v d x :