High Temperature Superconducting Magnetic Levitation
6 Ë 1 Fundamentals of superconductivity The Gibbs free energy can be obtained by the integral G(T,p,H)−G(T,p, 0 )= −휇 0 H X 0 Md ...
1.5 London equations Ë 7 The above discussion deals with the phase transition between the normal state and the superconducting s ...
8 Ë 1 Fundamentals of superconductivity where∇is the curl operator,Eis the electric field, andBis the magnetic field. We have 휕 ...
1.7 Coherence length Ë 9 For the special case of a semi-infinite superconductor with a flat boundary within free space, if the m ...
10 Ë 1 Fundamentals of superconductivity which the two electrons that constitute the Cooper pair. It refers to the space scale o ...
1.8 Critical current densities Ë 11 The coherence lengths휉of the HTSC materials have strong anisotropy. The con- ductivity along ...
12 Ë 1 Fundamentals of superconductivity The GL critical current density is expressed as [20] Jc= 훷^0 3 $ 3 휋휇 0 휆^2 휉 . (1.35) ...
1.9 Critical magnetic fields Ë 13 electrons becomes comparable to the energy gap 2훥, Cooper pairs are broken and superconductivi ...
14 Ë 1 Fundamentals of superconductivity The upper critical fieldHc2( 0 )of a type II superconductor is very high so that direct ...
1.11 Type II superconductors Ë 15 In type II superconductors, [22, 23] increasing the applied field more than the lower critical ...
16 Ë 1 Fundamentals of superconductivity play an important role to prevent the flux line from motion. The better the flux-pinnin ...
1.12 Specific characteristics of HTSC Ë 17 Axial symmetry is assumed for the case of in-planeaandbdirections, so that the screen ...
18 Ë 1 Fundamentals of superconductivity References [1]Onnes HK. Disappearance of the electrical resistance of mercury at helium ...
Further bibliography Ë 19 Further bibliography [1] Chu CW. Superconductivity. High-temperature encyclopedia of applied physics. ...
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Jia-Su Wang and Su-Yu Wang 2 Superconducting materials Superconductors are divided into conventional and unconventional supercon ...
22 Ë 2 Superconducting materials Fig. 2.1:Critical temperatures of superconductors from LTSC to HTSC [2]. Hc2are 14.5 T (Nb-Ti) ...
2.1 LTS materials Ë 23 Fig. 2.2:Critical current density of Nb-Ti, at 4.2 and 1.9 K, compared with that of Nb 3 Sn at 4.2 K [11] ...
24 Ë 2 Superconducting materials 2.2 LTS bulk materials There are no practical applications of LTS bulk superconductors, mostly ...
2.3 HTS materials Ë 25 cheap and easily handled liquid nitrogen as a cryogen has increased the range of practical applications o ...
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