Mc lcMc lc...1Li m u..2I. Hin tng siu dn.3 I.1. Khi nim hin tng siu dn....3 I.2.in tr khng.....3 I.3.Nhit ti hn v rng tuyn pha....4II. Cc vt liu siu dn..4 II.1. Vi nt v lch s pht hin cc cht siu dn...4 Bng thng k mt s vt liu siu dn.7 II.2.Tnh cht t.....7II.2.1. Tnh nghch t ca vt dn l tng.......................7II.2.2. Vt siu dn khng l tng................8II.2.3. Hiu ng Meissner...8II.2.4. T trng ti hn.....9 II.2.5. Phn loi cc cht siu dn theo tnh cht t....9 II.3.PHn bit gia vt liu siu dn v vt liu dn in hon ho............10III. Cc l thuyt lin quan n siu dn..............10 III.1.Entropi catrng thi siu dn v trng thi thng ...10 III.2.S xm nhp ca t trng vo cht siu dn...11 III.3.L thuyt BCS...11IV. Cht siu dn nhit cao..12V. Cc ng dng ca vt liu siu dn.............12 V.1. Tu chy trn m t...............12 V.2. My chp nh cng hng t (MRI)...........13 V.3. My gia tc ht bngcht siu dn nhit cao13 V.4.Truyn ti nng lng ( Electric Power Tranmission)...13 V.5.Bom E.....................13 V.6.Kh nng gi trng thi plasma..............14V.7.My pht in siu dn...14V.8.L phn ng nhit hch t..14V.9.Mt s cc ng dng khc..14Li kt..151Li m u ti Hin tng siu dn v nhng ng dng trong khoa hc i sng c nhm chng em nghin cu vi mong mun c nng cao hiu bit ca mnh v hin tng siu dn, nhanh chng tip cn vi nhng kin thc v nhng ng dng mi l ca hin tng ny trong khoa hc i sng Trong ti liu ny, chng em c trnh by v vi nt ca qu trnh lch s pht hin cc cht siu dn, nhng l thuyt lin quan, nhng khi nim, c im in hnh ca hin tng siu dn, vt liu siu dn v cui cng l nhng ng dng c th trong khoa hc i sng. C th gip cc bn c mt ci nhn c th hn v hin tng ny, v bit c nhng iu mi l, th v trong vic ng dng siu dn vo cng ngh hin i. Hy vng ti liu ny s l mt t liu b ch cho cc bn sinh vin, cng nh nhng ngi am m khoa hc c mong mun tm hiu thm v hin tng siu dn mt vn cn rt nhiu iu b n 2I. Hin tng siu dnI.1. Khi nim hin tng siu dnSiu dn l mt trng thi vt cht ph thuc vo nhit ti hn m n cho php dng in chayju qua trong trng thi khng in tr v khi t siu dn vo trong t trng th t trng y b y ra khi n.Hin tng siu dn l hin tng m in tr ca mt cht no t ngt gim v 0 mt nhit xc nh.Hnh 1.1S mt in tr ca siu dn nhit thpI.2. in tr khngV nguyn tc, di nhit chuyn pha, in tr ca cht siu dn xem nh hon ton bin mt. Vy thc cht: trong trng thi siu dn, in tr thnh khng hay l c gi tr rt nh? Tt nhin, khng th chng minh c bng thc nghim rng in tr trong thct l 0; bi v in tr ca nhiu cht trong trng thi siu dn c th nh hn nhy m cc thit b o cho php c th ghi nhn c. Trong trng hp nhyhn, cho dng in chy xung quanh mt xuyn siu dn khp kn, khi nhn thy dng in hu nh khng suy gim sau mt thi gian rt di. Gi thit rng t cm ca xuyn l L, khi nu thi im t = 0 ta bt u cho dng I(0) chy vng quanh xuyn, thi gian mun hn t 0, cng dng in chy qua xuyn tun theo cng thc :i(t)=i(0)etLR

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y R l in tr ca xuyn. Chng ta c th o t trng to ra dng in bao quanh xuyn. Php o t trng khng ly nng lng t mch in m vn cho ta kh nng quan st dng in lun chuyn khng thay i theo thi gian v c th xc nh c in tr ca kim loi siu dn c