We demonstrate Ramsey spectroscopy with cold 87Rb atoms via a two-photon Raman process. One laser beam has a cross-over resonant frequency on ...
Jou rna lo fth e Ko r ean Phy s i ca lSo c i e ty ,V o l .64 , No .5 , Ma r ch2014 ,pp .667∼671
Ram se ySpe c t ro s cop yb yD i re c tU seo f Re sonan tL igh tonI so tope A tom sfo r S ing le -pho ton De tun ing H oon Yu, M i HyunCho i, Y eL inMoon,S eungJ inK im andJung BogK im∗ D ep a r tm en to f Ph y s i c s Edu c a t ion , Ko r e a Na t iona l Un i v e r s i t yo f Edu c a t ion , Ch e on gwon363 -791 , Ko r e a (R e c e iv ed11 O c tob e r2013 ,infina lfo rm7Janua ry2014 ) W ed emon s t ra t e Ram s eysp e c t ro s copy w i thco ld 87Rba tom sv iaatw o -pho ton Ramanp ro c e s s . ran s i t ionandth eo th e rb eamha sa On ela s e rb eamha sac ro s s -ov e rr e sonan tf r equ en cyonth e 85Rbt 6 .8 GH zsh i f t edf r equ en cy . Th e s etw ola s e rb eam sfu lfi l lth etw o -pho tonRamanr e sonan c econd i t ion , wh i chinv o lv e sas ing l e -pho tond e tun ingo f −2 .6 GH z . Byimp l em en t ingth e s etw ola s e r sonco ld 87 Rba tom s ,w ed emon s t ra t e Ram s eysp e c t ro s copy w i thanin t e r roga t iont im eo fth ein t e rm ed ia t e s ta t ebyu s ingπ/2 Ramanpu l s e s .Inou rla s e rsy s t em ,w ecanchang eth es ing l e -pho tond e tun ingto ran s i t ionl in eu s eda salo ck ings igna landanin j e c t ed 1 .2 ,4 .2o r−5 .6 GH zbychang ingth e85Rbt s id eband . Th ela s e rsy s t emtha td i r e c t lyu s e sr e sonan tl igh toni so top ea tom sw i l lb ed e s c r ib edin th i spap e r . PACSnumbe r s :37 .25 .+k ,03 .75 .Dg K eywo rd s : Ram s eyspe c t ro s copy ,A tomin t e r f e rom e t e r ,I so topet ran s i t ion , RamanLa s e r DO I :10 .3938/ jkp s .64 .667
I .INTRODUCT ION S in c ei t sfi r s td emon s t ra t ionin1991[1–4 ] ,a tomin t e r f e rom e t ryh a sa t t r a c t edcon s id e rab l ea t t en t ionf o rp r e c i s em e a su r em en t so fin e r t ia leff e c t s . Th eg rav im e t e r , gy ro s c op e ,g r ad i om e t e r ,anda c cu ra t epho tonr e co i lm ea su r em en t s ,a sw e l la st e s t so fg en e ra lr e la t iv i tya r efun dam en t a lexp e r im en t sp e r ta in ingtoa tomin t e r f e rom e t ry [5–12 ] . H ow ev e r , du etoth ecomp l ex i tyo fth eexp e r im en t a lsy s t em ,th e s eexp e r im en t s hav ethu sfa rb e en confin edt ol abo r a to ryenv i ronm en t s . Inr e c en ty ea r s , w i thth er ap idd ev e lopm en to fth ea tom i c man ipu la t ion t e chn o l o g i e su s ed w i tha tom i cin t e r f e rom e t ry ,som ee f fo r t sh av eb e en und e r tak ento d ev e lop po r tab l ea tom in t e r f e r om e t e r sth a tcanb eu s edin m i c ro -g rav i tyand mob i l een v i r onm en t s[13–16 ] . Th e s eeffo r t sa r eexp e c t ed tol eadt oc on s id e r ab l eimp rov em en t sinth ea r eao fa tom in t e r f e r om e t ry . Th ew o rk in gp r in c ip l eo fana tomin t e r f e rom e t e ri s ba s edonth ew a v efun c t ion so fa tom i c l ev e ls ta t e s .S im i la rt oop t i c a lin t e r f e rom e t e r stha tcon s i s to fsp l i t t e r s and m i r r o r s ,a t omin t e r f e rom e t e r sa l so n e edsp l i t t e r s and m i r r o r s . W e l l -knownsp l i t t e r sand m i r ro r sfo ra tom in t e r f e r om e t e r sa r eimp l em en t edu s ingtw o -pho ton Ra mant r an s i t i on st ot ran s f e ra tom sb e tw e entw ohyp e r fin eg r ounds t a t e sv iaas t imu la t edRamanp ro c e s s . Th i s s t imu l a t edRam anp ro c e s ssup e rpo s e stw oa tom i cen e rgy s ta t e s . Wh enana tomi sin i t ia l lyp r epa r edinon es ta t e , ∗E -ma i l :jbk im@knu e .a c .k r ;F ax :
+82 -43 -235 -4273
th eπ/2pu l s esh i f t sth ea tomtoacoh e r en tsup e rpo s i t ionb e tw e entw os ta t e sw i thth esam eamp l i tud er a t i o . Th eπ/2pu l s e ,ca l l edab eamsp l i t t e r ,andth eπpu l s e , ca l l eda m i r ro r ,t ran s f e r sa tomf romth e i rin i t ia ls t a t et o ano th e rs ta t e . Ramanla s e rsy s t em sto g en e ra t e a Raman pu l s e , ing en e ra l ,con s i s to fsom e modu la to r s ,amp l ifi e r sand f r equ en cy lo ck ing d ev i c e s . In R e f s . 17 and 1 8 ,th e +1 s tandth e-1 s ts id eband so fth er e f e r en c eb e am w e r e g en e ra t ed w i th a h igh f r equ en cy a cou s to -op t i cm odu tomin t e r f e r om e t e r . la to r(AOM )t op rodu c ea85Rba In j e c t ion lo ck edla s e r so rtap e r edamp l ifi e r sw e r eu s ed fo ramp l ifi ca t iono fala s e rpow e r .In R e f s .15and1 6r e ga rd ingcompa c tandpo r tab l esy s t em s ,th eRam anl a s e r s tomin t e r f e rom e t e r . Aon e w e r ep rodu c edfo ran 87Rba f r equ en cys tab i l i z edex t e rna lcav i tyd iod ela s e r(ECDL ) w a su s eda sar e f e r en c ela s e r ,andtw os lav eECDL sand tw otap e r edamp l ifi e r sw e r eu s edto p rodu c eth eR a manl a s e rb eam s . Th etw os lav eECDL sw e r ef r equ en cy s tab i l i z edw i thanop t i ca lpha s e lo ck edl oopbyd e t e c t in g th ef r equ en cyd iff e r en c eb e tw e enth er e f e r en c eandth e Ramanb eam s . Mo s t Ramanl a s e r sfo ra tomin t e r f e r om e t e r sw e r e bu i l tbyu s ingth e s es ch em e s . As imp l e t e chn iqu eb a s edonasamp l e -and -ho ldc i r cu i t[ 1 9 ]w a s imp l em en t edtog en e ra t epha s e coh e r en tla s e rsy s t em . Inou rs ch em eu s ingd i r e c tl igh tr e sonan c ew i th85Rb 87 am a tom stop rodu c eth eRamanla s e rb eam sfo r RbR s eysp e c t ro s copy ,w eu s edon e ECDL ,on es l a v ed i od e la s e rtha tw a sop t i ca l lylo ck edbyin j e c t ion s e ed in g ,and on etap e r edamp l ifi e r . Inth i spap e r ,w ed e s c r ib eou r la s e rsy s t emandth er e su l t so fm ea su r em en t sw i thR am -
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F ig .1 . (Co lo ron l in e )(a ) En e rgyl ev e ls ch em eo fth e D2 t ran s i t ionl in eo fth e Rba tom s( ωm :f r equ en cyo fth e ma s id e :n ega t iv efi r s ts id ebandf r equ en cy ) . (b ) t e rla s e r ,ω1st s S ch ema t i co fth ela s e rsy s t em . Th ein s e ti sth eab so rp t ion sp e c t rumo fth e Rba tom s(SAS :sa tu ra t edab so rp t ionsp e c t ro s copy , HWP :ha l fw av ep la t e ,PBS :po la r i z ingb eamsp l i t t e r ,B .S . :b eamsp l i t t e r ,L :l en s , M :m i r ro r ,G :g la s s , FP I : F ab ry -P ´ e ro tin t e r f e rom e t e r , PD :pho tod iod e ,and PMfib e r : po la r i za t ion ma in ta in ingfib e r ) .
s eysp e c t r o s c op y .
I I . EXPER IMENTALSETUP Th eexp e r im en t a ls e tupfo rou rRamanb eam si sshown in F i g .1 .F i gu r e1 (a )p r e s en t sth een e rgyl ev e l so fth e 85 Rbandth e 87Rba tom i chyp e rfin es ta t e sandth ela s e r f r equ en c i e su s edinth e Ramanla s e r . Th een e rgyd iff e r rounds ta t e so f Rba tom scan en c eb e tw e enth e5S 1/2 g b eca l cu l a t edf r omth eab so rp t ionsp e c t rum ,a sshownin th ein s e tbo xinF i g .1 (b ) , wh i chshow sth es ch ema t i co f th ep r opo s edl a s e rsy s t em . W eu s edon eex t e rna lcav i ty d iod el a s e ra sth e ma s t e rla s e rtop rodu c eth e Raman . Th a t ma s t e rl a s e rw a saT op t i ca DL100 b eam sf o r87Rb la s e rsy s t emb a s edonth eL i t t rowconfigu ra t ion , wh i ch hadafun c t i ono fl o ck ingby modu la t ionandd emodu la t iono fth esp e c t rum . Th ef r equ en cyo fth e ma s t e r la s e rw a sl o ck ed u s ingth e Dopp l e r f r e esa tu ra t edab . Th e pow e r so fth e pump so rp t i onsp e c t rumo f85Rb andth ep r ob el a s e ru s edtoob ta insp e c t ra w e r eabou ta f ewt en so fµW ,r e sp e c t iv e ly . Th e ma s t e rla s e rw a ss ep a ra t edin t otw op a r t sth roughapo la r i z ingb eamsp l i t t e r (PBS ) .P a r to fth e ma s t e rl a s e rpow e r ,7 mW ,w a sd i r e c t edin t oane l e c t ro -op t i c modu la to r(EOM4851 -M , N ewF o cu s ) . An RFs igna lg en e ra t edf romasyn th e s i z e r
(MG3692A , An r i t su )w a sin j e c t edin toth e EOMa f t e r hav ingb e enamp l ifi edv iaan RFamp l ifi e r(AM 5 3 6 . 3 7 .3 -35 -35 ,M i c row av e Amp s . ) . Th eEOMp rodu c eds id e band sa t±6 .8 GH zonth e ma s t e rla s e rco r r e spond in gt o tom s . Th i s th eg round s ta t ehyp e rfin esp l i t t ingo f87Rba modu la t edla s e rw a sin j e c t edin toth ef r e e runn in gs l a v e la s e r . Th es lav ela s e rw a sf r equ en cy lo ck edonth efi r s t o rd e rs id ebandwh i l eth ega incond i t iono fth es l a v el a s e r w a s ma t ch edtoth es id ebandf r equ en cybyad ju s t in gth e inpu tcu r r en tandth et emp e ra tu r e . Th er ema in in gpow e r sinth e ma s t e rla s e randth ein j e c t ion lo ck eds l a v e la s e r sw e r espa t ia l lyov e r lapp edandth ens imu l t an e ou s ly amp l ifi edinas ing l etap e r edamp l ifi e r(EYP -TPA 0 7 8 0 01000 -3006 -CMT03 -0000 ,Eag l ey a rdPho ton i c s ) . Wh enth e ma s t e rla s e rw a slo ck edonth er e sonan tp eak )→ 5P ran s i t ionandth es l a v e o fth e85Rb5S1/2(F=2 3/2t la s e rw a sin j e c t ion lo ck ed w i thth en ega t iv efi r s ts id e band( th efi r s tpa r tinF ig .1 (a ) ) ,th etw ola s e r sfu lfi l l ed th etw o -pho tonRaman(TPR )r e sonan tcond i t i onf o rth e 87 Rba tom s . Th es ing l e -pho tond e tun ingw a sabou t−2 . 6 GH zinth i sca s e ,a sshowninth es e condpa r to fF i g . 1 (a ) . W ew e r eab l etoob ta inano th e rTPRr e son an tcon d i t ion w i th−5 .6 GH zs ing l e -pho tond e tun ing wh enth e )→ 5P r an ma s t e rla s e rw a slo ck edonth e5S1/2(F=3 3/2t s i t ion ,a sshowninth eth i rdpa r to fF ig .1 (a ) .B e c au s e th eEOMs imu l tan eou s lyp rodu c e s±6 .8 GH zs id eb and s , o th e rca s e sw i thd iff e r en tfo rm so fs ing l e -pho tond e tun ing ,a t4 .2 GH zand1 .2 GH zcanb eea s i lya ch i ev edwh en th es lav ela s e ri slo ck edonth epo s i t iv efi r s ts id eb andb y ad ju s t ingth einpu tcu r r en tw i thou tad ju s t ingth eb e am a l ignm en t . Inth i sexp e r im en t ,th e ma s t e rla s e rw a sl o ck edon 2 )→ th ec ro s sov e rr e sonan tt ran s i t ion85Rb5S1/2(F= ’=2 )and5P ’=3 ) ,andth es lav el a s e rw a s 5P 3/2(F 3/2(F in j e c t ion lo ck ed w i th th en ega t iv efi r s ts id eb and ,a s showninth efi r s tpa r to fF ig .1 (a ) . Thu s ,th es in g l e pho tond e tun ing w a s−2 .6 GH zinth i sca s e .Ino rd e rt o confi rmth elong i tud ina l mod e so fth e modu la t ed m a s t e r la s e randth etw oamp l ifi edla s e r s ,w eu s edah om em ad e F ab ry -P ´ e ro tin t e r f e rom e t e r(FP I )w i tha7GH zf r e esp e c t ra lrang e . T oimp l em en ttw o amp l ifi ed Ramanla s e r s onc o ld 87 Rbsamp l e ,w ein i t ia l lyload eda tom sina m a gn e t o op t i ca lt rap(MOT )fo r5s e cond sw i tha0 .1 T /m m a g n e t i cg rad i en tfi e ld .T oin c r ea s eth eload ingra t eandth e numb e ro fload eda tom sonth e MOTa tlowa tom i cp r e s su r e ,w eu s edu l t rav io l e td iod e sp la c eda roundth ePy r ex c e l lfo rth e MOT .B e cau s e UVl igh td e so rb srub id ium a tom sf romth e Py r ex w a l l ,th ea tom i cp r e s su r einth e v a cuumc e l lt empo ra r i lyin c r ea s ed[ 20 ] . Th ea t om i cm o la s s e sw a sfu r th e rcoo l edbyimp l em en t ingacomp r e s s ed MOTandpo la r i za t iong rad i en tcoo l ing(PGC ) . Th ea v e rag et emp e ra tu r eo fth ea tom i cc loud w a sm e a su r edt o b e(36±1 )µKb ytak ingab so rp t ionimag e swh i l ev a ry in g th et im eo ffl igh t . A f t e ra l lcoo l ingp ro c e s s e s ,w eop t i 1 )g rounds t a t e ca l lypump eda tom sin toth e5S 1/2(F= byi r rad ia t ingcoo l ingb eam sw i th−2Γd e tun in gf o r2 m sw i thou tar epump ingb eam . Th en a tu ra ll in ew id thΓ
Ram s eySp e c t ro s copyby D i r e c tU s eo fR e sonan tL igh t· · ·– HoonYu e ta l .
F ig .2 . (Co lo ron l in e )D iag ramo fth ev a cuumc e l lw i th t rapp ingandRamanb eam s . Th ec i r cu la r ly -po la r i z edRaman b eami s ho r i zon ta l ly p ropaga t ed andr e t ro r efl e c t ed . Th e p rob eb eami sov e r lapp ed w i thth ecoo l ingb eam s ,andth e fluo r e s c en c ei sd e t e c t eda tth etops id eo fth ev a cuumc e l l .
w a s6 MH z . F igu r e2sh ow sanexp e r im en ta ld iag ramo fth ev a cuum c e l lw i tht r app in gand Ramanb eam s . Th ec i r cu la r ly po la r i z ed Ram an b eam w a s ho r i zon ta l ly d i r e c t edand r e t ro r efl e c t ed . Th ew a i s to fth e Raman b eam w a s8 mm .Ino rd e rt om in im i z eth e ACS ta rksh i f t sindu c ed bytw ol a s e r sinth eRamanb eam s ,w ead ju s t edth epow e r ra t iob e tw e enth etw ob eam s . W ecou ldv a ryth era t io bych an g in gth einpu tpow e r so fth etw ola s e r sinth e tap e r edamp l ifi e r(TA )andcou ld m ea su r eth era t ioby mon i t o r in gth eFP Isp e c t rumo fth e TA ’ sou tpu tb eam . W ecou ldfindanop t ima lra t iotha tindu c ed m in imum ACsh i f tb ym e a su r ingth et ran s i t ionp robab i l i tya tth e sam epow e ro fth e Ramanb eamfo rea chpow e rra t io . A tth em in imum ACsh i f t ,th et ran s i t ionp robab i l i tyh a s a max imumv a lu ef o rab eam w i thth esam ein t en s i ty . Th r e ep a i r so fH e lmho l t zco i l sw e r ep la c eda roundth e c e l lf o rr ou gh m a gn e t i cfi e ldcomp en sa t ionandfo rth e p rodu c t i ono faqu an t i za t ionax i sfo rop t i ca lpump ing .
I I I . EXPER IMENTAL RESULTS tom st ran s F igu r e3sh ow sth epopu la t iono f 87Rba ( F = 1 ) s t a t e t o t h e 5 S ( F = 2 ) s t a t e f e r r edf r omth e5S 1/2 1/2 v iaas t imu l a t ed Raman p ro c e s s . A Raman pu l s eo f 60µs w a s app l i edtoth ea tom s . N ex t ,th e fluo r e s 2 )s ta t e wh i ch c en c ef r omth ea t om sinth e5S 1/2(F= 2 )→ 5P ’=3 )r e sonan tp rob el igh t , w a sb y5S1/2(F= 3/2(F w a sm e a su r ed . Th et ran s f e r r ed popu la t ion w a sm ea su r ed wh i l ech an g ingth e modu la t ionf r equ en cyo fth e EOM .B e c au s eth etw ola s e r sinth e Ramanb eamhav e th es am ec i r cu l a rpo la r i za t ion ,th es e l e c t ionru l ef o rth e 21 ] . tw o ph o t ont r an s i t ionin ou rca s ei s ∆m F = 0[ Th eth r e ep e ak sin F ig . 3co r r e spondtoth et ran s i -
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F ig .3 .P rofi l eo fa tom st ran s f e r r edv iaas t imu la t ed Ra man p ro c e s s . Th ep eak sa r er e sonan tt ran s i t ion sb e tw e en magn e t i csub l ev e l stha tco in c id ew i thtw o -pho tons e l e c t ion ,inou rca s e . Ea chpo in ti sth eav e rag eo f ru l e s , ∆m F =0 fou rexp e r im en ta lcy c l e s .
F ig .4 . Ram s eyf r ing e sshowth ed ep end en c eo fth epopu la 2 ,m 0 )s ta t efo r 87Rbonth ed e tun ing t iono fth e5S F= 1/2 (F= o fth e Ramanla s e r . Th ef r e ep ropaga t iont im eb e tw e enth e tw oπ/2pu l s e si s260µs .
t ion so f F=1 (m )→ F=2 (mF’= −1 ) , F= 1 (m 0 ) F=−1 F= ) ,andF=1 (m 1 ) → F=2 (mF’=+ 1 ) , → F=2 (mF’=0 F=+ r e sp e c t iv e ly .Z e rod e tun ingr e f e r stoth eEOMf r equ en cy 0 fo rth ep eaka s so c ia t ed w i thth em F =0 → mF’ = t ran s i t ion .Inadd i t ion ,th esp l i t t ingb e tw e enth ep e ak s r ep r e s en t sth eb ia s magn e t i cfi e ld ,240 mG ,fo rth equ an t i za t ionax i s ,andi t sd i r e c t ionco in c id e sw i thth ep r op a ga t ingd i r e c t iono fth e Ramanb eam . Th ep eakh e i gh t s ind i ca t eth ein i t ia lpopu la t iond i s t r ibu t ion so fth eh yp e r fin eZ e emansub l ev e l s . Th ea tom sw e r ep r epa r edev en ly a tth r e e magn e t i csub l ev e l sa f t e rop t i ca lpump in g . A f t e rth eop t i ca lpump ings tag e ,w eimp l em en t eda coup l eo fπ/2 Ramanpu l s e sw i thth et im ein t e rv a lb e tw e enth etw o pu l s e sb e ingsu i tab l efo rimp l em en t in g
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ta i lo fth ecu rv ei sth ef r equ en cyo fth es inu so id a lfun c t ion . Th e r ei sagoodag r e em en tw i thth er e c ip r o c a lo f th ef r e e ev o lu t iont im e . Inadd i t ion ,w ecanob s e rv ea pha s er ev e r sa ldu etoth ep r e c e s s iono fth eB lo chv e c t o r o fa tom s wh en T=360µsand T=560µs .
IV . CONCLUS IONS
F ig .5 . (Co lo ron l in e )D ep end en c eo f Ram s eyf r ing e son th ef r e ep ropaga t iont im e ,T . Th eso l idl in e sr ep r e s en tfi t t ing cu rv e so fth es inu so ida lfun c t ion ,andfi sth ef r equ en cyo fth e fi t t ingfun c t ion .
Ram s eysp e c t r o s c opy .F igu r e4show sc l ea ra tom i cRam s eyf r in g e s . Th efi r s t Ramanpu l s eo f60µs w a sapp l i ed toth ea t om i cc l oud . Inou rca s e ,th e60µspu l s eco r r e spond st oaπ/ 2pu l s e ;thu s ,th ew av efun c t iono fth e a tom si sd e s c r ib edb yth esup e rpo s i t ions ta t ew i thequa l p robab i l i t i e sb e tw e entw ohyp e rfin eg rounds ta t e s . A f t e r2 6 0µso ff r e eev o lv ingt im e(T ) ,as e condπ/2pu l s e w i thth es am edu r a t iona sth efi r s tpu l s ew a sapp l i ed . Th en ,a f t e r1 0 0µs ,ar e sonan tp rob eb eam w a sapp l i ed 2 )s ta t e . Ea ch top r ob eth epopu la t ioninth e5S 1/2(F= po in tinF i g .4r ep r e s en t sth eav e rag eo ffou rexp e r im en ta lcy c l e sund e rth esam eexp e r im en ta lcond i t ion s . Th e popu l a t i ont r an s f e r r edin toth e F=2s ta t ed ep end son th edu r a t i ono fth e Ramanpu l s eandonth etw o -pho ton d e tun in g . Th i sd ep end en c ec r ea t edtyp i ca l Ram s eyin t e r f e r en c ef r in g e s ,a sshownin F ig .4 . W eapp l i eda magn e t i cfi e ldo f3 1 0 mGtod efin eth equan t i za t ionax i s du r in gth een t i r ep ro c e s sfo r Ram s eysp e c t ro s copy . Th e f r equ en cyo fth e Ramanla s e rw a ss cann eda roundz e ro ,m 0 ) d e tun in gt ou s ea t om son lyinth e5S1/2(F=1 F= s ta t e . Th ea t om i c Ram s eyf r ing e sshowtha tou rla s e r sy s t emi sapp r op r i a t efo ru s einana tomin t e r f e rom e t e r . As imp l em od e ltoana ly z eth etw o -pho ton Raman t ran s i t i on w a su s edtot r ea tath r e e l ev e lsy s t ema sa tw o l ev e lsy s t emdu etoth eh ighs ing l e -pho tond e tun ing ’ ssupp r e s s in gth espon tan eou sem i s s ion . Th eo s c i l la t in gp r ob ab i l i tyo fth eupp e rg rounds ta t einth etw o l ev e lsy s t ema f t e rth eπ/2−π/2pu l s es equ en c ei sdu eto th ed ep end en c eo fa tom i cf r ing e sonth etw o -pho tond e tun in go fth eR am anb eam . Th eo s c i l la t ionf r equ en cyo f th epopu l a t i oni s1 /T ,wh e r eTd eno t e sth ef r e e ev o lv ing t im eb e tw e enth etw oπ/2pu l s e s . F igu r e5sh ow sf r ing es igna l sfo rv a r iou sf r e eev o lu t ion t im e sb e tw e enth eb eamsp l i t t ingpu l s e sw i thco r r e spond ing lyd iff e r en tf r in g ep e r iod s .E a chpo in tr ep r e s en t sth e av e ra g eo ff ou rexp e r im en ta lcy c l e s . Th eso l idl in efi t s th eexp e r im en t a ld a tatoas inu so id . Ea chfv a lu ea tth e
Inth i sr e s ea r ch ,w ed emon s t ra t ed a tom i cR am s ey tom sb yd i r e c t ly u s in g sp e c t ro s copy w i thco ld87Rb a l igh tonth er e sonan tt ran s i t ionl in eo fth ei so t op ea t om , 85 Rb ,a sth e ma s t e rla s e ro fa Ramanla s e rsy s t em . W e lo ck edth e ma s t e rla s e ronth ec ro s sov e rr e son an tt r an )→ 5P ’=2 )andg en e r a t ed s i t ion s85Rb5S1/2 (F=2 3/2(F a−6 .8 GH zs id eband by u s ing EOM . Th es l a v el a s e r w a sin j e c t ion lo ck ed w i thth es id eband s . Th e s em a s t e r ands lav ela s e r sfu lfi l lth e TPRcond i t ionfo r−2 . 6 GH z s ing l e -pho tond e tun ing . As ing l etap e r edamp l ifi e rs i mu l tan eou s lyamp l ifi edth epu l s e sf romth e ma s t e rand th es lav ela s e r stog en e ra t eth e Ramanpu l s e . Byap tom s ,w eob t a in ed p ly ingtw oπ/2pu l s e stoco ld87Rba a tomf r ing es igna l sfo rv a r iou sf r e eev o lu t iont im e sb e tw e enth etw opu l s e so fupto560µs .U s ingou rs ch em e , th es ing l e -pho tond e tun ingo fth e Ramanla s e rc ou ldb e ch ang edto1 .2 ,4 .2o r−5 .6 GH zbych ang ingth e85Rb t ran s i t ionl in eu s edfo rlo ck ingth ela s e rf r equ en cyo rb y ch ang ingth ein j e c t eds id eband w i thou tr e -a l ignm en to f b eam s .
ACKNO WLEDGMENTS Th i sr e s ea r ch w a ssuppo r t edbyth e Ba s i cS c i en c eR e s ea r chP rog ramth roughth e Na t iona lR e s ea r chF ound a t iono f Ko r ea(NRF )fund edbyth eM in i s t ryo f Edu c a t ion ,S c i en c eand T e chno logy(2012R1A1A2041 8 5 6 ) .
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