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Effect of Metal Ring Setting Outside HTSC Bulk. Disk on Trapped Field and Temperature Rise in. Pulse Field Magnetizing. Hiroyuki Fujishiro, Kazuya Yokoyama, ...
I E E ET RANS A C T I ONSONA P P L I E DS UP E RC O NDUC T I VI T Y , VOL. 1 5 , NO. 2 , J UN E2 0 0 5

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Ab s t r a c i -I no r de rt oe n ha nc et het r a ppe d丘e l di nc r y oI C O O l e d t T)di a g r m ,i a . e. ,byt hede c r e a s eo ft hec it r het e mpe r a t ur e( HTSCh ul kst l S ngpul i s e丘e l dma g ne t i z i ng( PFM) ,ame t a lr i ng i s s oc i a t e dwi ht t het e mp er a t ur er i s e.I n c lc a ur r e ntde ns i t yJca / o rAl )l l a Sbe e nt i g ht l ys e to nt ot heSm( s t inl a e s ss t e e l3 0 4and o r dert oe nha nc et heBT Pa ndQ;Va lue sbyPFM,t her e duc t i o n BaCuObul kdi s ka ndt l l er e l a t i o nbe t we e nt het o t a lt r a ppe d血ux o f h t e A T i s a n i n d i s p e n s a b l e i s s u e ・ T h e i t e r a t i v e l y ma g n e t l Z l n g 重言,t het r a ppe d丘e l dB言, a ndt het e mpe r a t ur er i s eAT, ha sbe e n p u l s e d 一 点 e l dme 血o dw i 也 r e d l l C i n ga mp l i t u d e( I MR A ) 【 5 ] , l o i n v e s t i g a t e da saf uI l e t i o no ft hea ppl i e dpul s ef ie l dBex・The重言 t l kl 6] ,aus eofvo r t e xt ypec o i l s a t i ngyokepi e c e sa r oundabt Pv lue a sa ree nha nc e da bo ut1 0-2 0%byt heme t lr a ingdue c a ndBT t ot her e duc t i o ni nt l l et e mpe r a t ur er i s eAT・ The s er e s ul t ss ug g e s t l 7]a ndamul t i pu ls et e c hm iquewi hs t t e pis w ec ool i ng( MPSC) o l t l l e瓜u xmo io t ni nt hepe ・ [ t l l a taPa rtO ft heg e ne r a t e dhe a tQduet 8]ha v ebe e na t t e mpt e dt os uppr e s st hehe a tge ne r a t i ond ur ing iphe r r lr a e g i o npr o mpt l yt r a n s f e r st ot heme t lr a inga t l dt hehe a t F M . A B 葺 c o f 1 7 . 2 4Ta t 2 9 Ki nY B a C u Ob u l kh a s b e e n r e P t r a n s f e rt ot hec o l ds t a g ei si mpr o v e dbyt her i ngs e t ing t . a hz e dbyFCM,e nha nc i ngt het he ma r lc onduc t i onoft heb ul k t nde xT e l ・ mS -Hi h Tcbul g ks upe r c o nduc t o r s , me t a l r i ngs e t t i n g , mpregnat ma lc onduc t i vi t ya l l oyi nt odr i ne d i ngahi gh血 e pl nnl nga ndv is c o usl o s s ,pul s e丘e l dmag ne t i z i I l g ,t e mpe r a t ur e byi hol e s[ 9] . me a s l l r e me nt . ss t udy ,wes e tame t a ldng( Aland/ ors t a i nl e s ss t e e l I n也i CuO bul kdi s k.Thef o l l owi nge f f e c t s 3 04)t i g ht l yonaSmBa Ⅰ .I NTRODUCTI ON k. a r ee xpe c t e df romt heme t a lr ings e tont ot heHTSCb ul kdi s r s t ,s i nc et hehea tge ne r a io t nd uet oPFM oc c ur sma in lyi n N oft hepr a c t i c la a ppl i ca t i onsofh i ghTcbul ks u- Fi heme t a lnnga t t a c he dt ot hebul kdi s k hepe iphe r r lr a e ion,t g pe r c o nduc t o r s( HTSCs )a sahi ghs t r e ng血 bul kma gne tf o r t iphe r r yc a ne a s i l ya ndpr c ・ mpt l yr e c e i vet hehe a t .Se c ond, ama g ne t i cl e vi t a t i o ns ys t e ma nds oo n, pul s e丘e l dma g ne t i z mg pe i nc et heab pl net a he ma r lc onduc t i vi yf t S a bi sf a rl a r ge rt ha J l ( PFM)a swe l la st hes t a t i c丘e l dc ool e dma gne iz t i ng( FCM)ha s s hec a xi sI C c,t hege ne r a t e dhe a tc a ne a s i l yr e a c ht heme t l a be e ni nt e ns i ve l yi nve s t l ga t e dbe c a us eo ft her e l a ive t l yc ompa c t t ns f e ingt m o血e inga longt her a di l pa a t hso ft hedi s k,t he ntra r , r ndi a ne xpe ns i ves e t up・The点e l dt r a ppe dbyPFM i s ,howe ve ol ds t a get hr o ug ht hehi hl g yc o nduc t i ver ing. Thes et woe fe c t s l owe rt ha nt ha ta t t a i ne dbyFCM a tt e mpe r a t u r e sbe l o w77K・ c e duc t i onoft hebul k. Fi na l l y, he t ho ldc u o nt ibut r et ot heAT r Thema i nr e a s onha sbe e na 仕r i but e dt o血el a r gehea tge ne r - s t lr a ings e t t i nghe l pst ome c ha iC m l1 a yr e i nf o r c et hebul kdi s k a t i onduet ot hedyna i m cmot ionoft hema gne iCf t luxa ga i ns t me [ 1 0 ] . ndt hev i s c o usf o r c eFv・ Weha ve t hevo r t e xpl nni ngf o r c eFp a

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ndt r a ppe d丘e l dB妄ont he s t udi e dt het e mpe r a t u r er is e△T a s ur f a c eo fc r yoc o ol e dYBa CuO a ndS mBaCuO bul ksdm i ng e d uc io t nf or PFM a ndpoi nt e doutt hei mpo r t a nc eo ft heATr t heB写e l1 n a nC e me nt[ 1 ] -[ 4] ・Thet ot l ge a ne r a f edhe a tQwa s e s t i ma t e dus i ngt hes pe c i iche f a ta oft heb ul ka ndt hema xi mum AT. I twaspoi nt e doutt ha tt heB;va l ue sa sf un ct ions o ft h ei ni t i a lt e mpe r a t u r eTsa nda ppl i e dpul s e丘e l dBe又c a nbe rs t oo don也 eba s i sof血et r a ppe d丘e l d( β革C)byFCM vs ・ u nde Ma n u s c np tr e c e i v e dOc t o b e r3 , 2 0 0 4 . Th i swo r kwa ss u p p o r t e dn ip a r t b y J a p a nS c i e n c ea n dT e c h n o l o g yCo r p o r a t i o nu nd e r t h eJ o i n t r e s e a r c hP r o j e c t f o r ur eo nDe v e l o p me n t o f p r a c t i c a l a p p h c a Re io g n a l ht e n s i v ei nt h el wa t eP r e f e c t t i o n so f ma g n e i tC丘 e l dt e c h n o l o g yf o ru s ei nt h er e g l O na n di ne v e r y d a yl i v l n g ・ , H.F u j i s h i r oa ndM.Ka ne y a maa r ewi ht t heF a c u l t yo fEn g i n e e ing r l wa t eUn i v e r s i qr , Mo io r k a0 2 0 8 5 5I , J a p a n( e 一 ma i1 : uj f i s h i r o @i wa , t e u ・ a c . j p ; t 2 2 0 3 0 0 4@i wa t e u ・ a c ・ j p ) , lI a n s t i t u t ef o rMa t e ia r lsS c i e n c e , Ts u k u b a , K・ Yo k o y a mai sw it ht h eNa i t o n 3 0 5 0 0 0 3 , J a p n( a e ma il : Yo k o y a ma . Ka z u y a @n i ms , g o j p ) . t hr MRAMa t e ia r lR&DCo . , I : TD. , 5 1 5 0Ha c h i k e n Jh o , Ka iy r a , TOk ai swi 48 0 0 2 1 , J a p n( a a ma i l : t o n@a k ii . is a i n ・ c o ・ j p ) . ng , I wa t eUn i v e r s i t y . Hei sn o w KNo t owa swi ht t heF a c u l t y' o fEn g i n e e i r wi hI t wa t el n d u s 由a lP r o mo t i o nCe n t e r ,Mo io r k a0 2 0 0 8 5 2 ,J a p a n( e 一 ma i1 : n o t o k o s b i c h i @y a h o o . c o j p ) ・ Di it g a lOb j e c t l d e if m i e rl o t 1 1 09 I T I AS C. 2 0 0 5 . 8 4 9 4 2 5 4

Ⅱ.Exp ERI MENT ALPRqCEDURE A hi g hl yc a x i so ie r nt e dS mBaCuO bul ks upe r c o nd uc t o r ( Do w且 Mi ni ngCo. ,Lt d)wi 血 45mm d i a me t e ra nd1 5Ⅱ皿 hi t c n es k swa sus e d.Thi sc ons i s t e d off ourg r o wt h s e c t or r e gi ons ( GSRs ) , di vi de d by 血e g r o w也 s e c t o r bo und,Th ebul ki sc ompos e dofSmBa2Cu3 0y a ie r s( GSBs )[ 2] ( Sm1 23 )a ndSm2 BaCuO5( Sm211 )wi ht t hemol a rr a ioo t f Sm1 23:Sm211- Il o :0・ 3,1 5. Owt L % Ag2 0powde r ,a nd O・ 5wt . % Ptpo wde r .Theb lk wa u su ni f o r i yi m mpr e g na t e d bye po xyr e s i ni n va c uum a ndt he nt hee poxyr e s i nl a ye ron hes t u r f a c eo ft hebu枚 di s kwa sr e mo ve d.Thes t a i le n s ss t e e l l )r A ingwi h 4mm i t nt hi c ne k s s ( SUS304)o rt hea l i num ( m a nd 1 5m ni n he i g ht ,wa sf ixe dont ot hebul k di s kus i ng a pl e Z OnNg r e a s e・ Wec l1t a her inga t t a c he ds a mpl ea sSUSSm o rA lSm・ Si nc eal a r gehe a tge ne r a ionduet t ot hee ddyc ur r e nt △T >6Ⅹ at100K) ,t her ingwa s t ookpl a c ei nt heA lr ing( l y, △T c utwi t haga pof1Ⅱ皿 a SS ho wni nFi g.1 .Re s ul t nt a hi t n O・ 2K・Si nc et heA l r ingdi dnot wa sd i im m is he dt owi c ont a c tt i g ht l ywi ht t hebu披 duet ot hega p,a not he rSUSr i ng

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F i g3 .Th ema x i mu mt e mp e r a t u r er i s e s△TBma xa n d△TRma xa t t h eb u l k F i g . 4 .Th et o t l t a r a p ed飢l p X軍 f o r e a c hme t lr a in gs e t t i n ga f t e r( a ) heNol t a n dt he r i n gf o r( a )t he No t a n d( b )No 5p u l s e sa saf un c t i o no fBex. Th e a b)t heNo 5p u l s ea p p l i c a t i o n , a saf un c t i o no fBex.Th et y p i c a lc o n i c l a n d( △TBmaxv lu a e sa r et hea v e r a g e do n e so v e r△TOmaxt o△T4 ma x . t r a p p e da e l dd i s t ib r u t i o n sB 各mmar ed i s p l a y e df o rt h eS US i r n gs e t t i n ga n d b a r eS mb l l l k . .

Auxpr e f e r e nt ia ll yi nt ud r e si nt ot heb u比 f r om t heGSRsc o nt a i ni ngP2,P3a ndP4a ndt hes ha r pa ndl a r get e mpe r a t ur er is e s ( △T -25K)t a kepl a c ewi hi t n3sa tt he s epos i t i o ns ・ T( i )r e c ove r st ot hei ni t i lt a e mpe r a t ur eTsa f t e r1 5-2 0m i n. T3( i )of SUSSm de c r e a s e sf a s t e ra f t e rt heT3( i )ma x i mum,a l t ho ug h t hema xi mum t e mpe r a t u r er is ei ss i il m a rt ot ha to fBSm.Thi s r e s ul tme nst a ha tapa r to ft hege ne r a t e dhe a tQpr o mpt l yt r ns a f e r st ot heSUSing. r Thema x i mu m ATv luea a tT3de c r e a s e s t 0-20Kf orAl Sm a ndWI Sm・Ther a t eo ft e mpe r a t u r ed e c r e a s e( -d T( i )/ dt )a f t e rt hepe a ki ss ma llf o rAl Smbutt ha t f o rh teWSmi sl a r gea n da lmos tt hes m ea a st heSUSSm. As f o rt hei t e r a ivepu t ls e丘e l da p pl i c a t i ons ,△T i st hel a r ge s tf o r heNolpul t s ea ndde c r e a s e sf ort hes uc c e e di ngpu ls e sl 2] ・ The i nc 一 e me ntoft het r a ppe d丘e l d△B妄i sa l s ot hel rge a s tf ort he Nolpul s e , f ol l o we dbyag r a dua li nc r e a s ef ort heNo 2a ndNo3 pul s es . Fort h eNo 5puls ea ppl i c a t i on, t heT( i )pea kdi s a ppe a r s f ora l lt hes e t t l ngS .ATi ss l i g ht l ys ma ll e rf o rt heSUSSm a nd WI Smt ha nf ort hebar ebu l ka ndA lings r e t t i ng, Fi g. 2( b)pr e s e nt st heTO( i )a t POf o re a c hme t lr a ings e t t i ng. TO( i )r is e su pl a t e s ta m ongTO - T4be c a us et hed i s t nc a e rom t f hema j o rhe a ts o u r c ei sus ua l l yt hel o ng e s tl 2] .Fort he SUSSma ndWSm, TO( i )r e a c he sama xi mu mf a s t e rtha nh ta t f orBSm. Th e s er e s ul t sme a nt ha tt hef luxmo t i oni se n ha nc e d i nt hec e nt r lr a e gl O nOft h eb u l kbyt heSUBSma ndWSm a nd t hema gne t i cf luxe sa r ea c c u mul a t e df a s t e ri nt heb ul kc e nt e r . Thea noma lous l yl o ngt imec o ns t ntf a ort het e mpe r a t u r er is e f o rt heA lings r e t t i ngma yr e s ul tf t o mt hehi ht g he ma r lc ont a c t r e s i s t a ncebe t we e nt heb ul ka ndA ling・ r Fi g.2( C )s ho wst heTR( i )f o re a c hme t lr a ings e t t i ng・The ma xi mum AT va lue sf o rSUSI Sm a ndWSm a r e1 2K a nd 1 0K,r es ec p ive t l y,a ndt het imec o ns t a ntf o rt het e mpe r a t u r e is r eo fTR( i )i sl on ge rf o rt heSUSSm a ndWI Smt ha nt ha tof T3( i ) . n et e mpe r a t ur er is ei nt heme t lr a ingi sma inl yduet o t hehe a tc onduc ionf t r o mt heb ul ka ndt het e mpe r a t ur er is ei nt he lA ingl r SS l owe rbe c a us eoft hehi g ht he r ma lc o nt a c t r e s i s t nc a e. Fi gs .3( a )a nd( b)s u m a iz r et hema xi mu m t e mpe r a t u r er is e o ft hebul kATBma xa ndt her ingATRrnax a f t e rt heNola nd No 5pul s ea saf unc t i o nofBex.ATBmax,t hea v e r a g e dva lue a t△TOma x∼△T4ma x , i nc r e a s e swi t hi nc r e a s i ngBe又f o rbot h

st hel a r ge s tf o rWI Sm a ndAl Sm;e. g. ,f r om heATBmax i t 23K. t o1 8Kf o rt heNolpu l s eofBe x- 4. 70T.ATRm a x ls a oi n甲e a S e Sw it hi nc r e a s l ngBe 又f orbo t hNota ndNo5pul s e s a n di sa bo ut5 0t o8 0%of△TBma x. △TRma xi st h el a rg e s tf o r t h eSUSinga r ndt hes ma ll e s tf ort h eWing, r het o t lt a r a ppe d且ux些 a ft e rt he Fi gs ・ 4( a )a nd4( b)pr e s e nt t Nota ndNo 5pu l s ea saf unc t i o no fBe x. Fo rt heNolpul s e ,壁 o fBSmi ss ma l l e s tf o re a c hBe又a n dt he鍔 Va lu ei se nha nc e d byt heme t a l r i ngs e t t i ng・ Es ec p i a l l y , f o rt heSUSSma ndWSm, t heQ;Va lue sa f t e rt he4・ 7 0Ta nd5・ 53Tpulse si nc r e a s ea bo ut 20%c o mpa re dwi ht t hos eo ft hebu l kwi t ho ut ing. r Thei nc r e a s e ma yma in lyc omef f o mt hede c r e a s eo ft het e mp er a t ur er is ed ue t ot her ings e t ing,whi t c hr e s ul t si nt hei nc r e a s eo ft hee fe c t i ve c it r iC lc a ur r e ntde ns i t y.TheQ;e n ha nc e me nti so bs e r v e df o r Al Sm,wh i c hs ugg e s t st ha tt hegoodt he ma r lc o nt a c tbe t we e n t her inga ndt heSmb ul ki sof vi t li a mpo r t a nc e. Thet r a ppe df ie l d B写mea s ur e da tPHi sa l s oe l1 n nC a e dbyt heme t a li rngs e t t i ng; f o re xa m pl e, B;( - 2・ 95T)f o rWSmi sa bo utl 0%l a r ge rt ha n ha t to fBSm ( -2. 71T)a f t e rt heNo5Pul s eofBe x-5. 53T. Thet y pi c lt a r a ppe df ie l dd i s t ibut r i o nsB imma r es howni nt he i ns e to fFi g,4( a )i nwhi c hac o n i c l 丘e a l dd i s t ibut r i onc n be a c on丘m e d. Ne le g c t l ngt hehe a td r ine a dt ot hec o l ds t a g e ,h tege ne r a t e d he a tQ byt hePFM o pe r a t i o nc n bee a s t i ma t e dus ngt i hef o1 l o wmge qua t i on, Ts+ △TBmax

Q-

/

( CBu,hVB u l k ) d T

Ts

T s +△TRn,ax

( CR g+ VR in



) dT,

ing

(1)



whe r eCBu l ka ndCRi n ga r et hes pe c i Bche a t( I/c m3 K) ,a nd VT Bu lka ndVRi n ga r et hev o l umeo ft heSmb ul ka ndt heme t l a in r g, r e s pe c t i v e l y . Fi g. 5s howst hee s t i ma t e dQva luesa saf unc t i onofBex f o re a c hme t lr a ings e t t i ng. Fo rt heNolpul s e ,t he Q va lueoft heb u比 wi he t a c hme t a lr ingi ss ma l l e rt ha nt ha t o f B S m ・ T h i s r e s u l t s u g g e s t s h t a t h t e h e a t t r a n s f e r r e d f r o m h t e Not a ndNo5pul s e s .△TBm警 O fBI Sm i st hel a r ge s ta ndi s ul ki spa r ia t ll yd r a ne i dt ot hec o l ds t a g et hr oug ht her ing・Fo r r e duc e dbyt heme t a lr ings e t t i ng.Es pe c i a l l y,t her e d uc t i ono f b

3 7 6 5

F UJ I S HT ROe T a L . : EFF E CTOFMET ALRI NGS E TT I NGOUTS I DEHTS CBULKDI S KONTR AP PE DF I EL DI NP FM

bul k. Thegoodt he m a r l conduct a ncebet weent hebul k





き 00

∴ , , I

+ 十

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ndt o per ipher ya n dr i ngl Sneces s a r yt Or educeAT a ues . enhancet he革 andB; val Themet a lr i ngwi t hahi ght hem a lconduct i vi t yal s o o enhancest het he- a l血a i nf ort hegener a t edheatQt t r ns a f ert ot hecol ds t age. AcKNOWLEDGMENT

M. I kebeofI wat eUni Theaut hor swoul dl i ket ot hankPr of . ve r s i t yf ort heva l uabl es ugges t i ons ・ 4

5

6

7

Bex( T)

REFERENCES

Fi g. 5. Th ee s t i ma t e dg e ne r a t e dhe a tQ a saf u n c t i o no fBe又f o re a c hme t a l in r gs e t t in g・ Th ei n s e ti n d i c a t e st heh e a tc a p a c i t yC o ft h eSmb u l k,SUS3 0 4 a n dAl . 血eNo5pul s e,TheQval ueofちSm i snea r l yt hes a meast he lQoft a hebul ka n dt hemet a lr ing, i r r es pect i veof _ t hes peci es t ot a ndvol umeoft hemet a lr ing. Thi sr es ul tmea nst hatt heheati s gene r a t edma i nl yi nt hebul kandi st r a ns f e r r edt ot hemet lr a ing nea r l ya di a ba t i cal l yf ort heNo5pul s e. Thehea taow t ot hecol d xi snots ol a r ge. s t agema yr emai ns mal li ncas eATBma

l V SUMMARY I nor dert oenhancet het r a pped丘el di ncr yocool edHTSC bul ksbyt hepul s e丘el dmagnet iz i ng( PFM)met hod,t heefect mBaCuO bul kdi s khasbeeni nofamet a lr i ngs eta r oundt heS

s ,t het r a pped ndt het emper a t ur er i s eAT f ort hes ucces s i veapRel d B; a pl i cat ionofpul s e丘el dsBe又wi t hva iouss r t r engt hs1mPor t a nt expe r i ment a lr es ul t sa ndconc l us i onsobt a i nedi nt hi ss t udya r e s umma izedasf r ol l ows . vet l ga t edbymeas ur ingt het ot a lt r a ppedf lux鍔

( 1 )

TheQ; a ndB; val uesar eenha n cedabout -20% byt hemet a lr i ngs et t i ngCOmPa r edwi t ht hos eoft he ba r ebul kwi 血out血emet alr i ng.Thema i nor l gl ni s hebul kdur ingPFM .Si nce t her educt ionofAT oft n t heper iphhehea t tgene r at i onmos t l yt a kespl acei a lr i ngs et ′ e r a lr egl OnOft hebul kdi s ki nPFM,血emet roundt a hebul ki smor eefect i vet ha nt hei ns er ionof t

( 2)

1 0

ahi gh一 也e ma Lconduc t i veal l oyon血ebul kcent e r . TheSUS-a ndW ( Al +SUS) ingsbehaveasagoodheat r educt i oni nt he r es e r voi rwhi chcont ibut r et ot heAT r

, T・ Oka ,K Yo k o y a ma . a n dK・ No t o ,' Ti mee v o l u io t na nd [ 1 ]H. Fu j i s h i r o s pa t i a ld i s t r i b u t i o no ft e mpe r a t u r ei nYBCOb u l ks u p e r c o n d u c t o ra 鮎r p u l s ef ie l dma g n e t i z l n g, "Su per c ond・ Sc i ・T e c hnoZ ・ , v o l . 1 6 , p p. 8 0 9 -81 4, 2 0 0 3 . [ 2 ]- , ` v r e mp e r a t u r er is ei nSmba s e db u l ks u p e r c o n d u c t o ra f t e ra p p l y i n g i t e r a i t v ep ls u e丘e l d s : ' Su pe r c ond. Sc i ・ T e c hnol ・ , v o l . 1 7, p p・ 51 5 7, 2 0 0 4・ [ 3 ]H. Fu j i s h i r o, T. Ok a ,K. Yo k o y ma a , M. Ka n e y a ma , ndK. a No t o, " Fl u x mo t i o ns t u d i e sb yme nso a ft e mp e r a t u r eme a s u r e me n ti nma g ne t i z i n g p r o c e s s e sf o rHTSCb u l ks , MI EEEAppl .Su j ? e T I C On d, v ol .1 4, n o . 2, p p. 1 0 5 4 -1 0 5 7, 2 0 0 4. 1H F u j i s h i r o , K・ Yo k o ya ma , M, Ka n e ya ma , T. Oka , a n dK. No t o , H Es [ 4 ma t i o no fg e n e r a t e dh e a ti np u l s e丘 e l dma g n e t i z i n gf o rSmBa Cu Ob u l k s u p e r c o n d u c t o r , "Ph ys i c aC, v o l ・ 41 2 41 4, p p・ 6 46 -6 5 0, 2 0 0 4. 1 5 ]U.Mi z u t a n i ,T.Ok a ,Y.I t o h,Y.Ya na i, g M. Yo s h i ka wa ,a n dH.kut a, u Pu l s e ie f l dma g ne t i z a io t na p p l i e dt oh i g hTcs u p e r c o n d u c t o r s , ' ヲ Appl . d . , v o l .6 , p p. 2 3 5 2 46 ,1 9 98 . Su peT I C OT 7 [ 6 ]HII k u t a , H・ I s hi ha r a ,YI Ya n a gi ,Y/ I t o h ,a ndU. Mi z u t a n i ,… Ex t r a c t i n g t h eu t mo s tf r o mt h eh i h pe g r f o r ma nc eo fSmBa Cu 0b u l ks u p e r c o n d u c t o r sb yp u l s e鮎l dma g n e t i 2 : a t i o n, "Su pe r c ond・ Sci .T e c h . , v o l . 1 5 , p p. 6 06 -61 2, 2 0 0 2 , ki , Y・ Ak i t a , M・ I 2 : u i, m H. Su imo g t o,Y. Ho n d o u,Y. [ 7 ]T・ I d a , H・ Ma t s u z a Ki mu r a , N. Sa ka i , S. Na iki r , I . Hi r a b a y a s h i , M. Mi ki , M. Mu r a ka i, m a nd M・K it a n o," Ma g n e iz t a t i o np r o p e r t i e sf o rGd Ba Cu0b u l ks l l p e r Cn d u c t o r swi t h' ac o u p l eo fp u l s e d 一 点e l dv o r ( e x t y p ec oil s , MPh ys z ' c aC, v o l ・ 41 2 41 4, p p.6 3 8 -6 4 5 , 2 0 0 4・ [ 8 】M.Sa nd e r ,u Su t t e r ,R・ Ko c h,a n dM.Kユ a s e r , " Pu l s e dma g n e t i z a t i o n o fHTSb ul kp a r t sa tT < 77I t, MSu pe T I C Ond.Sc i ・T e c 九, v o l t1 3 ,p p・ 8 41 -8 45 ,2 0 0 0 . at ur es u pe r c o n d u c t o rb u l k I : 9 ]M・ To ml t aa nd , M・ Mu r a k a mi ," Hi g h t e mp e r ma g n e t st ha t c a nt r a pma g ne t i c丘 e l d so fo v e r1 7t e s l aa t29K, "Nat uy e , v o l . 421 , p p・ 51 7 -5 20 , 2 0 0 3 ・ [ 1 0 ]M・Mo it r aeEal ・ ,` Tr a p p e d丘e l da n dme c h a n i c a lp r o pe r t i e so fQMG ma g n e t , "i nP7 1 0C ・1998I nt ・Wor k s ho pSu pe f l C Onduc t i v i y, t To k yo ,1 9 9 8 , p p.1 1 5 -1 1 8 . [ 1 1 ]H・ Fu j i s h i r oa n dS・Ko hd y a s hi ," Th e r ma lc o nd u c t i vi y,h t te r ma ld i f f u s i v i t ya n dt h e mo r e l e c t icp r o we ri nSmba s e db u l ks u pe r c o n d u c t o r s , " I EEET7 ' anS ・ Appl .Su pe T I C O1 7 d l , VO l 11 2, p p・1 1 2 4 11 1 2 7, 20 0 2・ k e be , H・ Fu j i s h i r oI T・ Na it o,a ndK No t o, " S i mu l t ne a o usme a s u r 9 1 [ 1 2 ]M・r me nt o ft he r ma ld i f f u s i it v ya n dc o n d u c t i v i t ya p p l i e dt oBi 2 2 2 3c e r a mi c s u pe r c o n d u c t o r s , "J ・Pk ys ・Soc ・ J pn . , v o l ・ 6 3 , p p・ 31 0 7 31 1 4,1 9 9 41 ti-

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