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Improved Apparatus for Studying Coherent Optical Transients.

Don C. Elbers

Published Jan 1, 1976• 0 citations
Publisher

Abstract

c u l a r l y a p p r e c ia te h i s w illin g n e s s to allo w me to conduct my program as I saw f i t , to make my own d is c o v e r ie s and m is ta k e s , and n o t say " I to ld you so" when th in g s ran amuck.I a ls o w ish to than k B i l l Thomason f o r h is in v a lu a b le c o l la b o r a t io n in p o r tio n s o f th e e x p e rim e n ta l work and f o r th e g r e a t i n t e r e s t and p a tie n c e he d is p la y e d th ro u g h o u t o ur a s s o c ia t io n .I w ish to thank P r o f e s s o r Dorr R alph, who i s a n ev er-en d in g so u rce o f ob scu re y e t im p o rtan t in fo rm a tio n , fo r h i s encouragem ent, and a s s is ta n c e in many a s p e c ts o f th e e x p e rim e n ta l work.F u r th e r , I would li k e to thank th e members o f my com m ittee f o r t h e i r i n t e r e s t and s u g g e s tio n s in t h i s work.The te c h n ic a l a s s i s t a n c e , s u g g e s tio n s , and e x p la n a tio n s pro v id ed by Leo Jo rd an and Les E delen have proven in v a lu a b le in th e co m p letio n of t h i s p r o j e c t .O ther members o f th e s t a f f who have done more than t h e i r jo b s r e q u ire d a re th e "gang" i n th e C o lleg e machine shop headed by Joe C ass, and W alter P a tz ig , w ith o u t whose e f f o r t s I would s t i l l be w a itin g f o r new equipment to a r r i v e .My m o th er, f a th e r and b r o th e r a re due s p e c ia l thanks f o r t h e i r c o n tin u ed encouragem ent, love and m oral su p p o rt th ro u g h o u t my educa t i o n a l c a r e e r .I a ls o w ish to thank my b r o t h e r , Buddy, fo r h is a s s is ta n c e in p ro v id in g the p h o to g rap h ic e x p e r t is e n e c e ssa ry to rep ro d u ce many o f th e o s c illo g ra m s ap p ea rin g in t h i s d i s s e r t a t i o n .I a p p r e c ia te th e in v a lu a b le h e l p , lo v e , and encouragem ent of Kathy (G ro ssin ) d u rin g th e co u rse o f t h i s work.I am g r a t e f u l f o r th e f i n a n c i a l a s s is ta n c e in th e p r e p a r a tio n o f t h i s d i s s e r t a t i o n which was p ro v id ed by th e C h arles E. C oates M emorial Fund o f th e L o u isia n a S ta te U n iv e rs ity F o u n d atio n .

DOI
10.31390/gradschool_disstheses.3013

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c u l a r l y a p p r e c ia te h i s w illin g n e s s to allo w me to conduct my program as I saw f i t , to make my own d is c o v e r ie s and m is ta k e s , and n o t say " I to ld you so" when th in g s ran amuck.I a ls o w ish to than k B i l l Thomason f o r h is in v a lu a b le c o l la b o r a t io n in p o r tio n s o f th e e x p e rim e n ta l work and f o r th e g r e a t i n t e r e s t and p a tie n c e he d is p la y e d th ro u g h o u t o ur a s s o c ia t io n .I w ish to thank P r o f e s s o r Dorr R alph, who i s a n ev er-en d in g so u rce o f ob scu re y e t im p o rtan t in fo rm a tio n , fo r h i s encouragem ent, and a s s is ta n c e in many a s p e c ts o f th e e x p e rim e n ta l work.F u r th e r , I would li k e to thank th e members o f my com m ittee f o r t h e i r i n t e r e s t and s u g g e s tio n s in t h i s work.The te c h n ic a l a s s i s t a n c e , s u g g e s tio n s , and e x p la n a tio n s pro v id ed by Leo Jo rd an and Les E delen have proven in v a lu a b le in th e co m p letio n of t h i s p r o j e c t .O ther members o f th e s t a f f who have done more than t h e i r jo b s r e q u ire d a re th e "gang" i n th e C o lleg e machine shop headed by Joe C ass, and W alter P a tz ig , w ith o u t whose e f f o r t s I would s t i l l be w a itin g f o r new equipment to a r r i v e .My m o th er, f a th e r and b r o th e r a re due s p e c ia l thanks f o r t h e i r c o n tin u ed encouragem ent, love and m oral su p p o rt th ro u g h o u t my educa t i o n a l c a r e e r .I a ls o w ish to thank my b r o t h e r , Buddy, fo r h is a s s is ta n c e in p ro v id in g the p h o to g rap h ic e x p e r t is e n e c e ssa ry to rep ro d u ce many o f th e o s c illo g ra m s ap p ea rin g in t h i s d i s s e r t a t i o n .I a p p r e c ia te th e in v a lu a b le h e l p , lo v e , and encouragem ent of Kathy (G ro ssin ) d u rin g th e co u rse o f t h i s work.I am g r a t e f u l f o r th e f i n a n c i a l a s s is ta n c e in th e p r e p a r a tio n o f t h i s d i s s e r t a t i o n which was p ro v id ed by th e C h arles E. C oates M emorial Fund o f th e L o u isia n a S ta te U n iv e rs ity F o u n d atio n .
in g the o n s e t of d is s ip a tio n at th e ro to n c r i t ic a l v e lo c ity in s u p e r flu id h e liu m .T h is is a c la s s ic a l , c o r r e s p o n d e n c e -p r in c ip le -lim it po in t of v iew and is q u ite an alo g o u s to th e c la s s ic a l d e s c r ip tio n that i s w idely a c c e p te d fo r u n d e rs ta n d in g the e m is s io n of photons by an e le c t r i c c h a rg e th a t m o v e s at a c o n s ta n t v e lo c ity g r e a t e r th a n the sp e e d of lig h t in a d ia le c tr ic m e d iu m .A fte r f i r s t d e riv in g a th e o ry f o r th e w ave e x c ita tio n s and b o u n d a ry -v a lu e p ro b le m s of the c o rre s p o n d e n c e p rin c ip le lim it fo r a co n d en se d -b o so n s y s te m , th is p a p e r show s th a t a w ave r a d i a tio n field f o r m s a ro u n d a fo re ig n body m o v in g th ro u g h the s u p e r fluid m e d iu m w hen the fo re ig n body m o v e s f a s t e r th an the m in im u m p h a se v e lo c ity , {w/k )m jn » w ave e x c ita tio n s in the m e d iu m .M o re o v e r, the sp a tia l d e p e n d e n c e of th is w ave fie ld and the lo s s of e n e rg y r a d ia tin g th ro u g h it a r e c a lc u la te d a s fu n ctio n s of the f r a c tio n a l in c r e a s e of the fo re ig n b o d y 's v e lo c ity above the th r e s h o ld v e lo c ity In s p ite of a p p ro x im a tio n s m a d e in th e c a lc u la tio n s , th e r e s u l t s in d ic a te th a t it is im p o s s ib le , e x p e r i m e n ta lly , to f o r c e an io n c o m p lex to m ove th ro u g h the s u p e rflu id c o m ponent o f h e liu m a t a v e lo c ity o b s e r v a b ly g r e a t e r th an th e ro to n c r i t i c a l v e lo c ity .ACKNOWLEDGMENTS I would lik e to thank P r o f e s s o r R. L. M ills fo r h is c o n trib u tio n s to m y g ra d u a te ed u catio n and fo r h is p e rc e p tiv e c o u n s e l w hile th is r e s e a r c h w a s b e in g c o n d u cted , e s p e c ia lly r e g a r d in g th e re s o lu tio n of s e v e r a l m a th e m a tic a l d iffic u ltie s w hen no so lu tio n s s e e m e d to e x is t.T h e N a tio n a l A e ro n a u tic s and Space A d m in is tr a tio n i s th an k ed f o r i t s fin a n c ia l su p p o rt d u rin g the y e a
D erivation o f th e Lorentz Transform ation.Views o f E in s te in on Space, Time and Sim ^iltaneity.Minkowski' s 4-dim ensional a n a ly s is .In v a ria n ce o f Maxwell' s E quations under a L orentz T ran sfom atioE M echanics i n %>ecial R e la M v ity .The Doppler E ffe c t i n S p e c ia l R e la t iv it y .Transform ation o f T ensors in s p e c ia l R e l a t i v i t y .QÜANTIM THK)RY De B r o g lie Theory -Ssqpeiiment^l v e r i f ic a t io n .P ï l n d p l e s o f M echanics and O p tic s .^ Germat -Hamilton Comparison between th e Developm oit o f Theory in M echanics and O p tic s .Schrodinger* s Equation.S o lu tio n o f equation fo r t i e o s c i l l a t o r and t i e Hydrogen Atom.Meaning o f Wave and Gioup V e lo c ity .I k ic e r t'in ty R e la tio n .R ela tio n between H eisenberg and Schrodinger.P a u li' s I n c lu s io n o f %)in.H rac* s E quation.Dirac T h ^r y o f th e E lec tro n in th e Atom.In v a ria n ce o f th e D irac Equation.N eg a tiv e Energy S ta te s .if€c^x)ic& iind 0;jtics I r t h e s e tw o b r a n c h e s o f r^olenoe, t h e phenom ena, w h ich in th e c o u r s e o f t l r -e , f i r s t came t o be s t u d i e d , w ere t h o s e le r i; e s c a l e o r m a c r o s c o p ic e f f e c t s w h ich o b tr u d e thtansel^m s upon th e s e n s e e * T h is wae s o i n M e c h a n ic s, t h e s t u d y o f m a tte r in m o tio n and i n e q u ilib r iu m , w here b o d ie s a t l e a s t ccsm aT uble i n s i s e w it h t h e human body and m oving s lo w ly enough f o r t h e i r m o tio n t o be s t u d i e d , f i r s t came u n d er c o n s i d e r a t i o n , and i n L i g h t , w here th e atud^' o f th e m a c r o s c o p ic q u a l i t i e s l e d t o G s fx a e tr lc a l O p tic s* Laws w ere fo r m u la te d w h ich w ere i n a c c o r d w it h th e known phcRonena u n t i l f ; r t !i e r s tu d y b r o u g h t s m a ll s c a l e phenomena u n d er o b e e r v e t io r * H ere d i f f i c u l t i e s w ere fo u n d , b o th w here t h e b o d ie s w ere e x ti'e m e ly s m e ll and ivhere m o tio n was v e r y g r e a t* I t seem s u n d e r s ta n d a b le t h a t i f th e b e h a v io u r o f th e v e r y u io a lle s t p o r t io n s o f t h i n g s i s known, th e n l y a k in d o f a d d i t i o n i t may be p o s s i b l e t o f i n d t w la w f o r la r g e e f f e c t s and t h a t th e s t a t i s t i c a l la w s o o b ta iiw id may n o t show tW i n t r i c a c i e s o f th e l a u s f o r th e i n d i v i d u a l p a r t s * A ls o we c a n im a g in e t h a t v a r io u s p ^o ssib le la w s o f b e h a v io u r f o r th e i n d i v i d u a l s c a n le a d t o th e same s t a t i s t i c a l law* I n a d d i t i o n , i t h a s b egu n t o be u n d e r sto o d t h a t we c a n n o t make e x a c t m easurem ent on a l l a s p e c t s o f a p h y s ic a l, p rob lem a t t h e aaae t im e , aikl t h a t -1 « th o u g h , i f we a re c o n t e n t w it h a r o u g h ly c o r r e c t a n sw er we may 4 f i n d a c o n s i s t e n t f o r m u la t io n a law f o r t h e w h o le b e h a v io u r o f A a b o d y , y e t i t now seem s t h a t i f we c o n c e n t r a t e upon one p a r t i c u l a r a s p e c t and su c c e e d i n a n e x p la n a t io n o f t h a t , i t w i l l n o t be p o s s i b l e t o e x p la in o t h e r a s p e c t s i n th e same te r m s .I n b o th M ech a n ics and O p tic s we have a d u a l i t y i n t h a t t h e r e i s b o th a c o r p u s c u la r and wave a s p e c t o f e a c h t o b e c o n s id e r e d .The r e a l d ev elo p m en t o f b o th M eciian ics and O p tic s a s s c i e n c e s i n t h e s y s t e m a t ic form i n w h ich we u n d e r sta n d them , b egan i n th e 1 7 th c e n t u r y , th o u g h lo n g b e f o r e t h a t tim e t h e r e w ere t h e o r i e s o f M a tte r and o f L i g h t , some o f w h ich b e a r d i s t i n c t r e sem b la n c e t o v ie w s now h e l d .O f t h e s e we may n o te th e A tom ic th e o r y due t o D em o critu s o f th e 5 t h c e n tu r y B .C .a c c o r d in g t o w h ic h , a l l s u b s t a n c e s , s o l i d s , l i q u i d s , g a s e s o r l i g h t w ere c o r p u s c u la r i n n a tu r e and t h e i r b e h a v io u r became e x p l i c a b l e by th e m o tio n s and i n t e r a c t i o n s o f t h e s e 'a to m s * .The c o r p u s c le s th e m s e lv e s w ere i n d i v i s i b l e and w ere th e u lt im a t e u n i t s o f n a t u r e .I t i s t o be s e e n t h a t a s i n g l e u n d e r ly in g p r i n c i p l e w as p o s t u la t e d f o r th e b e h a v io u r o f b o th M a tter and L ig h t a t t h i s t im e .I n t h e 3 r d c e n tu r y B .C .A rch im ed es, i n h i s s tu d y o f m ech a n ics was m a in ly co n ce rn ed w it h S t a t i c s and h e w as
The method of s e n s itiz e d flu o re sc e n c e was used to d e t e r mine cro ss s e c tio n s f o r th e v ario u s e x c i ta t io n t r a n s f e r p ro cesses 2 2 occuring in K -Rb vapour m ix tu res and f o r ** ^3 /2 ™i%ing and 2 2 2 ^1^2 ^1/ 2 ' ^3 /2 quenching in rubidium induced in c o l l i s i o n s w ith se v e ra l d iatom ic and polyatom ic m olecules in t h e i r ground s t a t e s .The a l k a l i vapour in th e flu o resce n ce c e l l , which was kept a t low p re s s u re s to avoid s e rio u s e f f e c t s o f r a d ia tio n im prisonm ent, was ir r a d i a te d by one component of th e a p p ro p ria te resonance d o u b le t.The r e s u ltin g flu o re s c e n c e , which c o n s is te d o f the w avelength component p re s e n t in th e e x c itin g li g h t (resonance flu o re sc e n c e ) and th o se components which aro se from th e em ission by atoms c o l l i s i o n a l l y p o pulated ( s e n s itiz e d flu o re s c e n c e ), was reso lv ed and observed a t r ig h t an g les to th e d ir e c tio n o f th e in c id e n t beam.Measurements of s e n s itiz e d -to -r e s o n a n c e flu o re s c e n t in t e n s ity r a t i o s in r e l a t i o n to rubidium vapour p re s s u re y ie ld e d the fo llo w in g cro ss s e c tio n s fo r e x c i ta t io n t r a n s f e r in K -Rb vapour m ix tu re s: ^1 2 ' ( ^^^1 /2 = 40 f , Qgg, (K4^P^yg ^ Rb$^P^yg) = 2 ?Q i^,(K 4^Pi/2 -, Rb$2p^yg) = 2 .7 Qg^,(K4^Pgyg -Rb^^P^y^) = 1,9 qJ_2(k4^Pi/2 -K4^P^yj = 260 f , and Q^'(KA^P^y^ -KA^P^y^) = 175 In m ix tu res o f rubidium w ith m olecular g a s e s , measurements o f the i n t e n s ity r a t i o s in r e l a t i o n to gas p re s s u re s gave the fo llo w in g c ro s s s e c tio n s fo r th e mixing and quenching c o l l i s i o n s .