Nghiên cứu vật liệu siêu dẫn nhiệt độ cao loại bi sr ca cu o

- LUC LUC Trang MO DAU ^ ChjjTD'n^ I - VE VAT LIEU SI2U DAN ?IHIET TJO OAO (Tong quan t h y c nghifm v a l y t h u y e t ) Ve qua t r i n h p h a t h i | n c a c c h a t s i e u d a n ^0 1«2, Ket qua thirc nghi|ra cua h | sieu dan n n i f t dQ cao khong chira dat hilm ^2 1.2.1 Sisu din nhiet d^ cao Bi-£r-Ca-Cu-0 1»2.1.1 Thanh phan cua h% sieu dan n'r.l | t d§ cao Bi^Sr.,Ca.|Cu20^ 1.2.1.2 Cau true tinh the cua h^ sieu dan nhi^t dg cao lo§i 3i23r2Ca-Cu20 a) Cau true tinh thi cua hq^p chat sieu dan ^^2^^2^® ^'^2'^8 * b) Cau true tinh t.ie oua hq-;, v^^t si-^u dan Bi2Sr2Ca -^ ^^2^3-6 1.2.2 oiau dan nhi^t cao Tl-Ba-Ca-Cu-0 >I2 '\5 ^7 ^7 49 2\ a) He? chat Tl.j3a^Ca^Cu20^ 2i b) Eo'p chat Tl25a2Ca^Cu20g 22 ^ 1.2.3 Cac txnh chat siiu dan cua hq-p chat Bi-3r-Ca-Cu-0 va Tl-Ba-Ca-Cu-C 24 1.2.4* ^ac hq*p chat siau dan pha tgp t r e n cc so' Bi-Sr-Ca-Cu-0 va Tl-Ba-Ca-Cu-C 1»2.4.1 Pha tqp he sieu dan Bi-3r-Ca-Cu-C 1,2.4«2 Pha tap Iron^ hC eiSu dor Tl-Ba-Ca-Cu-O 1.3» So sanh tinii chat va cau true sieu dan Y-3a-Cu-0 va Bi-3r-Ga-Cu-0 27 27 29 30 1.4» IviOt so mo hinh ly thuyst g i a i thfch hi^n tur;'n.g sieu dan nhi'it d? cao 33 Ma dau 33 ! • J^j t h u y e t H'/3, Ly t h u y e t tu'c^ng t a o s i e u t r a o d o i Chu'cn- I I 34 36 - lYOT SO IT^T COiIQ l^(^li:L CHZ TAO VAT LIZU SIEU DAiT IIHIZT DO CAO LOAI B l - ^ r - C a - C u - O Mo* d a u ^^ 2.1 Cac phiro'ng phap cong nghe che tao vat li|u sieu dan nhiet d^ cao '^2 2.2 Qui trinh che t§o vat li|u sieu dan nhi|t d$ cao CO phan 3i.jSr^Ca-jCu20^ va Bi2Sr2Ca.^Cu2C,, 44 2.3 K| thong su* ly nhiet ^^ 2.4 anh huo'n^ cua cac che dQ sii ly nhiet va moi trucng len nhiet T^ 46 2.5 ^6t vai nhan zet Ket Iu|n 48 51 Chuo'nr III - CAC PHUOIiG PHAP THUC i^GHIZLl iJGMI^IJ CUU SILU DAIT i^HIET DO CAC 3.1« Phep dien trc' 53 3-2 iie phan tich nhiet vi sai (DTA) o' nhi«t dc thap 54 3»2.1 LIo ta thiet hi 3.2.2 Nguyen tac 3.2.3 PhuD'ng phap va sai so phep ^^ ^^ 57 3.3 He nhiet dung trcng vung nhi|t 4,2K den 3CGK Ka dau 58 3.3.1 U6 ta thiet >•; ^-v 3.3.2 Phiro'ng phap 3.3.3 Ket qua thu nghicm va sai so 59 ^iG4 Ket luin ^-^ Chu-Q^?: IV ' "^'OP CHAT SIEU DAN IJIIIET DO CAO LOAI B i - S r - C a - C u - O - 4 ^ chat sieii d'an n'aiet G5 cao Bi Sr.Ca.Ou^O^, 1.1.' Che t^o mau • Thu'c nghien , , ^ e t qua v^a t h a o l u a n a) Cau t r u e b) Cac txnh chat di^n va t u cua top c h a t s i e u cfan He s i e u dan n h l ^ t dO cao Bi^Sr^Ga.Cu^O LIuc d i c b n.:;hien cuu he s i e u dan BigSr^Ca^Cu^O^ 4.3 65 65 G5 66 e bat kip buo'c phat triln cue mot nganh khoa hqc mo'i, duei su chi d?o cua Giao su Than Due Hien, phong tni nghiem nhiet thap Trueng Dsi hoc Tcng hc^ He Noi de bat tay vao nghien cuu ve che t^o v^t li|u sieu dan nhiet ceo ngey tu mo'i nhan duq'c cec tncng tin nong hei cue "lucng gio sieu dan nhiet dg cao" tren the gic'i thci vao Viet Nam " Tneng 4- 1957 Pncng thi nghiem nhiet dg tnap de che tao duq'c vat li^u sieu dan r±.ief d§ cac loai Y-Be-Cu—G (123) co nnlet ;-.uyen z:hB T > 9011 Theng 4.19S6 Phong thf nghiem de t?o d'JO'C hr-p chat sieu dan nhi§t ceo lo§i Bi-Sr-Ce-Cu-0 vo'i hai nhiet chuyen pha T^^ - 110K ve T^g * ^^K Z"6^ Ban luan en ney d|t muc dfch la nghien cuu vat li^u sieu dan nhift dg cao loai Bi-Sr-Ca-Cu-0 (khong chua P-E) nham : - Nghien cuu oui trinh cong nghe de che teo vat lieu sieu dan nhiet ceo - Nghien cuu ca'c'tinh chat vat ly cue vat lieu.^Tira hieu m^i quan h^ giua cong i^jHie ve cec txnh chat cue vat lieu gcp phan hieu biet ve cec chat sieu dan nhiet cao H| Eieu dan nhiet cao ng-uyen (khong ]:e c;:v) Ei-3rCc Cu-O cao goru cec nguyen to re lien, ce kiem va co r±z.\:y e - 9Vi^t Nem, Vat lieu khong chua cac nguyen td dat hiem nhung tinh sieu dan cua no tueng ddi on d^nh khong khi,dong tho'i vat lieu lei cd nhift chuyen pha T cao ' * c -iOChuen^ I VE VAT LIEU SIEU DAN NHIET DO CAO (Tong Quen thuc nghicm va ly thuyet) Lich su phat minh cac chat sieu dan nhiet ceo, cac kit qua thuc nghiem tren cac h§ sieu dan nhiet d9 cao kh5ng chua dat hiem, m§t sd mo hinh ly thuyet gili thfch co' che sieu dan nhi^t d9 cao hien ney ve kha nang ung dung cue sieu dan nhi§t cao duo'c trinh bay mot each tong quen tror^g chuong 1.1 Ve Que trinh phat hi^n ce'c chat sieu dan Co the noi su phat hien Heli long la tien de cho su phat mi:Jx cac chat sieu dan Nam 1868 hei niha bac hgc Jancen va Locker /""97_7 da quen sat thay nhung vach 1§ cua anh sang m^t trei Do la v^ch quang phd Heli Hai muD'i nam sau nguei ta tim thay khf heli tren trai dat Nam I9O8, Kamerlingh - Onnes - nha bac hgc He Lan da hda long duo'c heli Ba nam sau, cung chfnh ong de phat hi§n hi§n tu^'ng sieu dan lan dau tien Phai den 25 nam sau, nam 1933, mgt vai nuo'c khac tren the gic'i mo'i che t§o duq'c heli j.dng, Ngu'ei ta da ggi heli long la "chat nuec luq'ng tu" vi nhieu tfnh chat dac biet cua nd /_ S7_7 Sau hien tueng sieu dan duec phat hien e Eg^ hang loet chat sieu dan mo'i dnr'o r^het hi^n them tronp vnnp* nhiet dO Heli long (4,2K) nliir : ciai (7.2K), 1^5 (9.2K), iroO (10,510, 1^ NbN (14.7K), NbjSn (18,1R>, 1^-Al-Ge (20-21K), NbGa (20.3K), NboGe (- 24K) fT'iZj Nhu vfy, thei gian dai tu nam 1911-1985 chat long heli van la m5i trueng nhat de nghien cuu va ung dung cac chat sieu dan Tfnh sieu dan chi ton tgi vung nhift d^ heli long da h§n che vi|c tirng dung chat sieu dan vao thuc te vl v^y , gan 3/4 the ky qua cac nha khoa hgc tren khap the gio'i da khong ngxsn^ tim toi nham phat hifn cec chat sieu dan cd nhiet chuyen phe ceo ho*n, Sy phat hien tfnh sieu dan hep chat gom Le-BaCu-O cue J.G Bednorz va K.A, Litlller / 12_7 da me cua va dua cac nha khoa hgc sang mgt linh vuc mo'i day trien vgng va hap dan la : sieu dan niiiet dg cao ! Cho den ney, cac hq*p chat gdm sieu dan nhiet cso cd the phan lam loai chfnh £'1\ ; 72_7 1) Loai hq»p cha% sieu dan chua La : La-Cu-O, La-Ba-Cu-O, La-Sr-Cu-0 cd T^ - 30-40K (nam 1986) 2) Loai hq'p chat sieu dan chua Y : Y-Be-Cu-0, RZ-Ba-Cu-0 cd Tc z 80-95K (nam 1987) 3) Lo§i sieu dan chua Bi : Bi-Sr-Ca-Cu-O cd nhi|t dg T - 80-120K (nam 1988) 4) Loai sieu din chua Tl : Tl-Ba-Ca-Cu-O cd T - SO-iZ^K c — (nam 19B8) 5) Loei sieu dan khong chua Cu : Ea-PI-Bi-O, cd T 30K (nam 1988) - 20- j I Hai loai gdm sieu d.in duec nhieu tac gia quan tam la hop chat sieu dan (123) chua ^ ho§c dat hiem (RE) va hq'p chat sieu dan cnua Bi hoac Tl (khong chua dat hiem) cd the dung gian sau day minh hga cho cac moc lich su phat hi^n cac chat sieu dan dac ti^ung va qua trinh iiL ^ cao nhiet d^ chuyin pha cue chung / 13_7 (^inh 1) Trong thap ky 90 cac nha khoa hgc dang chay dua vi§c tim kiem sieu dan nhift phong va cao ho*n nham « « dua cac kha nang ung dung vao khoa hgc va doi song Lac du heng tram lo?i gom sieu dan du-o'c phat hi^n va xac Uli^n bang th^'c nghieii-, nhung ve ce che ly thuyet hoan thien cue nd van dang Is van de tranh luan soi noi Co rat nhieu mo hinh ly thuyet Iihac dua de giei thich ve co' che sieu nhif.t dg cso cd nhung ly thuyet mau thuan nhau, tham dan chf trai nguxj'c 1.2, Net cua thuc nrhi^m cue cec hg sieu dan nhi^t ceo khong chua dat hiem De phuc vu cho cac nghien cuu cue chung toi, gio'i hgn ban luan an nay, chung toi chi tong ho;p cac ket qua thuc nghi|m tren v^t lifu sieu din nhi|t dg cao lo§i Bi-Sr-Ce-Cu-O, Tl-Ba-Ga-Cu-0, dac biet di sau ve hep chat sieu dan nhiet dg cao"loai Bi-Sr-Ca-Cu-O 1.2.-' Sieu dan rixiet c^-o Bi-Sr-Ca-Cu-^O, Hq'p chat sieu dan H luaeda va dong nghiep phat hifn thang 1.198S Day la lo§i hep chat sieu dan mo'i, da phe Hau het ce'c ket qua nghien cuu deu khang d4nh :hc;p chat eieu dan Bi-Sr-Ca-Cu-O chua ft nhat la hai pha sieu dan Pha thu: Xx- XLA '1/ 1 3i K - 1' a_2 -^ -A BLS^',Gl^_;^ 1' I 111 ! 100 BCI,,^CU20H UK] I I I 1 1 m 1 200 I 1 250 "ILiltSS^ Pu^Mtrd va Ue so tii koa a.c caa Ei-Sr i^Cci^_^ S a x ) C a X =^ O J O , O.20 j 0.30 • 1 300 RCTyR(30OK) 60 I ^ ! 100 I I I i \ 150 I I I — I — I — I — — t 200 250 300 T(K) X :=z o - ^ o j 0.50 a ) Vc'i X;^;0.30, ca'c ho;p chat BiC-Sr._^^BcjGoGu.^C, va BiorrG9. 32 )Gu.;C, deu la sieu dan khoi GfiU:ig chue it nhat la pha sieu dan vei cau true t'.' giac Pha siau d !.: ciinli cac h;p chat la (2212) giong nhu hqp chat sieu dan Bi-jp-Ga-Gu-O b) Vei x ^ 0.40, hc-p chat Bi(3r Ba )GaGu20 I ""X X ^ J xuat hien pha sieu dan thu eo nhiet d§ chuyen pha T^< 65r: va vat lifu chuyen dan ba'n dan o* X J^ 0.45 Trong ho.^ chat Bi3r(Ca- Ba )Cu^O "X X , dac trung sieu dan hoan toan bien d Zi mat a X ^ 0.40 Difn trc' cua cac mau bieu hifn gan giong ban dan e vung 120Z T < 3C0K va vinig T < 120K dien tro' khong thay doi c) Gae biln doi dac trur-g sieu dan ca hai hf hc'p ch'^t ''^:;":-'- /-:i -' '^.^nn la su* kaa'c ve kich thuee z „ : Ba'^"^ , Sr""*" va Ga"^ hc'pchat gay nen £ c^, 6S_/ d; '2hln tich kit qua BTA nniet cao cho biet cac pha sieu dan d'j^;e tao vung nhiet tu 820 Z din ScG ' '* • ^ KIT LUAIT Ga'c k e t qua c h i r J i cua ban l u a n van du-c'c r u t r a l a : Trong t h e i g i a n t i e n hanh lem l u f n van da xay du-ng duec : t l : i ' ^ bi- : d i f n t r e , n h i e t dung va BT ^1 ^ ca'c mau s i ^ u dan va ca'c mau kha'c Ca'c hf co the au dung dl khao s a t ca'c d$c t i n h n h i f t , d i f n va t u cua ca'c mlu t r o n r v u r ^ n h i e t t u 77-3CC'K ca t r o n g t u t r u e n g tu' - IKOc Ba che tao duec hang loat m::.u sieu din nhiet d; ceo loei Bi-Sr-Ga-Gu-0 (khong cliu'a dat hi-l'n) va mo- vei he^n 0.xa TDha taocua no nhu Bi(Sr^ Ba )C3:iuX 1-" va 3i5r(C3 ^•- y X 3.i )C' 1-x ' X z (X ^ 0.35) C=r- ;:-u chat lueng tot, c6 nhiet b^t dau chuyin sang trang tha'i sieu dan len tc'i 120K Ba clring to raiig cac tinh chat sieu dan cue v|t lifu chua Bi va cac mau chua Bi co phs tap Ba rat nh$y vc'i qui t n n h cSng nghe, dac biet la che su ly nhift doi vc'i ca'c mau Xac dinh dux;'c nhift hinh tharJi cac pha sieu dan cac mau neu tren o* tror^g vung 840 G - 860 C Cac liqp chat sieu dan enua Bi (1112), (22l2)va cac hc^ chat sieu dan chua ^i pha tap i:a, deu tnucc sieu i " 11 Glv, ".' e.r'.^ra xz nhat • ^i la hai oha sieu ian vei cac nhiet bat dlu e/.u-^^en ona T ^ = 111-12::: tucn,: -un.^ vei oha (2213} va cI T , = aG-~C:-:, txan- unx- vai o h a ( 2 ) Gau t r u e t i n h t h i cua c2 ' ' ca'c o h a s i e u dUn ( 2 ) va ( 2 ) c h u n " e h i k h a c n h a u ve gia t r i deu eo' d o i xxln:^ tu ca'c hKn.z s o mang t h e gia'c, —»- •• - /-> - >I00 TAI LI3U THA:.I KHAO T13i:0 VIBT K a r i a k i u I J I , K.JT Buxtrov, P : : I-Cirsev Sach torn t S t Ve v^.t l y , IlgiTca d i c h B^ng Quang Khane IT x u a t ban IChoa hpc va 'Xy t h u a t Ha ITpi 1971 iTiUyen n i u 3ue Luan an PTS, DHTH, Ha Hoi r^oS guyen Huy Sinh, Than Bt'c Hien Tfp e h i rlhoa hoc, DHTH - Ha Hei, So ( l ? S ) 2l Hguyln l-iuy S i n h , Than Due Iiien, I-Ioa Van Khanh T^p c h i Khoa hoe, DHTH - Ha Hoi, So ( l - ) 30 Hguyln Huy Sinh, Than Buc Hien, Hoa Van Khanh Tpp chi Khoa hoe, DHTH - Ifa Hoi, So ( l 9 ) 2o TI3rHCT HGA S Ead::^ S.A., B/.I 7aa:-03CKKfi TexKOJiori!£ npo33BO,i;CTBa Sepi'iTOE ii pa.-x:ioicepai'.mioi I'locKBa "BHcm?^ HixOJia" ' rojiojicd' • J.' ^^"'^- ^ : i , H.A npHTHOsa, Torauio, J[.U TymeBsn, Z.'L H.M EiwaKCi'^Ji nacLi/ia B I3T5 TDM 48 (I9SS), S:4 - > ( ^ - I I TISITG AHH : Anderson P.V/, Science 235, (19S7) 1195 Anshukova H.V, A I Golovashkin, O.H Ivanenko, i^.V K r a i s k a y a , K.V I^iitsen, P.H Lebedev, P h y s i c a 0.153-155, ( l 8 ) 625 iO BaerieL - S e e l e a c h e r and Guenther S c h i n d l e r P h y s i c a C 153-155 ( 3 ) i iA» Baskaran G, Zou Z and Anderson 2.17 S o l i d S t a t e Gommun 63 (1987).973 12 Bednorz J G ' and K.A I.l\!LLler Z r h y s 364, (l98&), l89 13 Bednorz, J Georg and K, Ale::^ I l ^ l e r Advanced M a t e r i a l s Hobel L e c t u r e , Angev/, Ghem 1CO, Hr ( 8 ) , 764 ^oz.^ 14 E e t l o g g B P h y s Rev L e t t vol 58, (19S7) 15 E e t l o g g B, T.T P a l s t r a , L.T* Schnesneyer, R Van Dover and R J Cava P h y s i c a C 153-155 ( i S S a ) 16 Border ? , J J 1052 Gapponi, G G h a i l l o u t , J Ghene^as A.'iV Hewat, S* A Hev/at, J L Hodeau, P L e j a y , II.LIarezio, A S u b p i c e , J L Tholence, R T o u r n i e r , D Tranqui I n t conf L a g n e t i s n P a r i s J u l l y (1988) 124 17 Border P , J J Capponi, G h a i l l o u t , J Ghenavas, A.'7 Hewat, B.A Hewat, J L Hodeau, LI H a r e z i o , J L Tholence, D T r a n q u i , P h y s i c a G 153-155 ( l o ) 62316 Gapcne B.'.V, D G Hinks and J D J o r g e n s e n Appl P h y s L e t t 50, ( l ? ) 543 19 Gava R J , R Van Dover, B Betlogg oinl B.A F'* etn^n, r h y s Rev L e t t 5^ ( ) 408 2.0 G h a r l e s K i t t e l I n t r o d u c t i o n t o s o l i d s t a t e P h y s i c s F o u r t h B d i t i o n by Jobji IViley Sons, i n e ( l l ) 3992d Gnu G.17, P.I-I I-Ior, R.L llen^f Huang, J Y.Q V/ang, L Gao , Z J B e c h t o l d , K P o r s t e r Ph:,'S Rev L e t t 5S ( l ) 1981 22 Ghu G.V/, P H , I-lor, R.L Ueng, L Gao, J Huang and Y.Q V/ang P h y s Rev L e t t 58 (1937) 4O5 23 Ghu CV/, J B e c h t o l d , L Gao, P.H, Hor, J Huang, R.L, I.-eng, Y.Y Sun, Y.':^ V/ang t^^:'^.': : -5 Plli's, Rev L e t t 60 ( 8 ) 24 Ghu G.V.', P H , l-lor, R.L I.leng, Z J Huang, L Gao, Y.Y.Hue, Y.Y Sun, Y.Q Wang and J Bechtold P h y s i c a C 153-15^; ('i9S3) 1135 I 25 Ghu G.V/, Bechtold J , Gao L , Hor 1- H, Huang S J , Lleng R.L, Sun Y.Y, V/ang Y.Q and Xue Y.Y Phys Rev L e t t 60 (1938) 491 26."'pyrot LI S o l i d S t a t e Gomnun 62, (l987) , 27 'Gyrot Li, D, Hayou, J P J u l i e n and F , Gyrot - LaOKnann, J Phys : Gondens Mater JU ( l 9 ) 4359 28 E i j i Takayania, nuromachi, Y o s h i s h i g e , Uchida, J p n J ^ Appl P h y s Vol 27 (1988), L , 5 29 P i h e r R A, J B Gordon, S, Kim, IT.3 P h i l l i p s and A.H S t a c y PlTysica G 153-155 ( l 8 ) i092 30 Gao L, , J Huang, R.L Meng, P.H Hor, J , Bechtold, '^Y,Y, Sun, G.^7 Chu, Z.2, Sheng and A.Ll Hermann L e t t e r s t o H a t u r e vol 332 (1988) 623 i Ginsberg D.H, S I n d e r s h e e s , H.B Salar.:on HiT'=; Goldenxeld, J P Rice and B.^ Pazol P h y s i c a G 153-155 ( r ? 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