Rare earth doping effects on superconducting properties of MgB_2:A review
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摘要
Rare earth(RE) elements and their compounds have been doped into MgB_2 since the discovery of the superconductivity of MgB_2. The doping effects of RE elements and RE compounds are summarized in terms of different doping methods and the accompanying variations in the superconducting transition temperature, upper critical field, irreversibility field, and critical current density(Jc). Conclusions are drawn on the doping mechanisms to demonstrate the possibility of improvement of Jcin the future. REBy phase inclusions are observed in MgB_2 as nano-pinning centers with significant enhancement of Jcin MgB_2 doped with Y, La, Dy, Ho, Nd, etc. Furthermore, some REs with larger magnetic moments will provide more efficient flux pinning centers with larger pinning forces, which is different with the doping effects and mechanism of ferromagnetic transition metals in MgB_2. The co-doping effects of RE with other dopants are also reviewed due to the multiple advantages of different doping mechanisms.
Rare earth(RE) elements and their compounds have been doped into MgB_2 since the discovery of the superconductivity of MgB_2. The doping effects of RE elements and RE compounds are summarized in terms of different doping methods and the accompanying variations in the superconducting transition temperature, upper critical field, irreversibility field, and critical current density(Jc). Conclusions are drawn on the doping mechanisms to demonstrate the possibility of improvement of Jcin the future. REBy phase inclusions are observed in MgB_2 as nano-pinning centers with significant enhancement of Jcin MgB_2 doped with Y, La, Dy, Ho, Nd, etc. Furthermore, some REs with larger magnetic moments will provide more efficient flux pinning centers with larger pinning forces, which is different with the doping effects and mechanism of ferromagnetic transition metals in MgB_2. The co-doping effects of RE with other dopants are also reviewed due to the multiple advantages of different doping mechanisms.
Rare earth(RE) elements and their compounds have been doped into MgB_2 since the discovery of the superconductivity of MgB_2. The doping effects of RE elements and RE compounds are summarized in terms of different doping methods and the accompanying variations in the superconducting transition temperature, upper critical field, irreversibility field, and critical current density(Jc). Conclusions are drawn on the doping mechanisms to demonstrate the possibility of improvement of Jcin the future. REBy phase inclusions are observed in MgB_2 as nano-pinning centers with significant enhancement of Jcin MgB_2 doped with Y, La, Dy, Ho, Nd, etc. Furthermore, some REs with larger magnetic moments will provide more efficient flux pinning centers with larger pinning forces, which is different with the doping effects and mechanism of ferromagnetic transition metals in MgB_2. The co-doping effects of RE with other dopants are also reviewed due to the multiple advantages of different doping mechanisms.
引文
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19.Aldica G,Popa S,Enculescu M,Badica P.Enhancement of critical current density and irreversibility field by Te or TeO2 addition to MgB2 bulk processed by spark plasma sintering.Scripta Mater.2012;66(8):570.
20.Batalu D,Aldica G,Popa S,Miu L,Enculescu M,Negrea RF,et al.High magnetic field enhancement of the critical current density by Ge,GeO2and Ge2C6H10O7additions to MgB2.Scripta Mater.2014;82:61.
21.Mustapic M,De Silva KSB,Aboutalebi SH,Barua S,Xu X,Wang J,et al.Improvements in the dispersion of nanosilver in a MgB2matrix through a graphene oxide net.J Phys Chem C.2015;119(19):10631.
22.Ionescu AM,Aldica G,Popa S,Enculescu M,Sandu V,Pasuk I,et al.Spark plasma sintered MgB2co-added with c-BN and C60.Mater Chem Phys.2016;170:201.
23.Cheng F,Ma ZQ,Liu CX,Li Hj,Shahriar A,Hossain M,et al.Enhancement of grain connectivity and critical current density in the ex-situ sintered MgB2superconductors by doping minor Cu.J Alloys Compd.2017;727:1105.
24.Kim JH,Dou SX,Shi DQ,Rindfleisch M,Tomsic M.Study of MgO formation and structural defects in in situ processed MgB2/Fe wires.Supercond Sci Technol.2007;20(10):1026.
25.Ranot M,Kang WN.MgB2coated superconducting tapes with high critical current densities fabricated by hybrid physical-chemical vapor deposition.Curr Appl Phys.2012;12(2):353.
26.Qaid SAS,Alzayed NS,Shahabuddin M,Ramay SM,Atiq S.The role of sintering conditions on the superconducting parameters of MgB2.J Mater Sci Mater Electron.2017;28(19):14696.
27.Prikhna T,Shapovalov A,Eisterer M,Shaternik V,Goldacker W,Weber HW,et al.Pinning in high performance Mg B2thin films and bulks:role of Mg-B-Onano-scale inhomogeneities.Physica C.2017;533:36.
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29.Soltanian S,Horvat J,Wang XL,Munroe P,Dou SX.Effect of nano-carbon particle doping on the flux pinning properties of MgB2 superconductor.Physica C.2003;390(3):185.
30.Katsura Y,Shimoyama J,Yamamoto A,Horii S,Kishio K.Effects of rare earth doping on the superconducting properties of MgB2.Physica C.2007;463e465:225.
31.Yeoh WK,Kim JH,Horvat J,Xu X,Qin MJ,Dou SX,et al.Control of nano carbon substitution for enhancing the critical current density in MgB2.Supercond Sci Technol.2006;19(6):596.
32.Ojha N,Malik VK,Bernhard C,Varma GD.The effect of Pr6O11doping on superconducting properties of Mg B2.Phys Status Solidi A.2010;207(1):175.
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