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Melting Point 1068 1085 1060 1046 1040 1010 1005 1005 990 960 (± 5Oc)

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Melting Point 1068 1085 1060 1046 1040 1010 1005 1005 990 960 (± 5Oc) IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. Recent progress of REBCO HTS bulk Xin YAO DtfPhi&AtDept. of Physics & Astronomy, Shanggg,hai Jiao Tong Univ. 1 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. RE in La Nd Sm Eu Gd Dy Ho Y Er Yb (RE)Ba2Cu3O7 Melting point 1068 1085 1060 1046 1040 1010 1005 1005 990 960 (± 5oC) ---- 95 93.5 93 92.5 92 92 92 92 92 Tc (K) PO2 PO2 PO2 PO2 air air air air air Jc @77K; 1T ---- 40-50 40-50 50-60 20-30 xKA/cmx KA/cm2 Birr (T); 77 K ---- 8–10 6 - 8 6 - 7 5 - 6 Better suppgperconducting performance 2 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. Potential of LREBCO (LRE=Nd,Sm..) bulks • Advantages compared to YBCO: 1600 ※ Exhibit better superconductivity 1500 High THigh T 1400 cc erature (K) Nd pp T P = 1359K (3. 2 at. % Nd) Sm T P = 1333K (1.8 at.% Sm) High JHigh Jcc at a high applied magnetic field Tem 1300 Y T P = 1278K ( 0.6 at.% Y) at. % Y at. % Sm ※ High growth rate at. % Nd 1200 0 2 4 6 8 due to high RE solubility in solvent at. % Nd, Y and Sm • Problems to be solved : 9 ※ Formation of solid solution (LRE1+xBa2-xCu3Oy) due to LRE/Ba substitution, leading to low Tc ※ Lack of suitable seed due to high peritectic temperature T p 3 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. 1. Oxygen1. Oxygen--controlledcontrolled growth 4 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. NdBa Nd Cu Ba CuOO 1+x 1+x 22--xx 33 77--yy NdNd--BaBa--CuCu--OO syyystem x p(O22), T= constantT= constant 2. CompositionComposition--controlledcontrolled growth 5 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. 95 K SmBCOSmBCOgrowngrown in 1 atmoxygen pressure by TSSG Supercond. Sci. Technol. 17 (2004) L47 SmB CO123CO1,2,3 crystals grown from d ifferent liquid with Ba/Cu =0.50,0.52,0.54 3. TemperatureTemperature--controlledcontrolled growth 6 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. RE in La Nd Sm Eu Gd Dy Ho Y Er Yb (RE)Ba2Cu3O7 Melting point 1068 1085 1060 1046 1040 1010 1005 1005 990 960 (± 5oC) ---- 95 93.5 93 92.5 92 92 92 92 92 Tc (K) PO2 PO2 PO2 PO2 air air air air air Jc @77K; 1T ---- 40-50 40-50 50-60 20-30 xKA/cmx KA/cm2 Birr (T); 77 K ---- 8–10 6 - 8 6 - 7 5 - 6 Cation stoichiometry of Sm123 is more controllable: Wide growth window in liquid composition and oxygen pressure 7 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. EffectsAddition of adding of BSm242 BaBa--richrich Sm secondaryBa22 Cu44 Baphase22 CuOO9 phase phase onocessedpr airon air on--processed airSmBCO ocessedprSmBCO SmBCOsuperconductor bulks Supercond. Sci. & Technol. 2009 Optimized addition of Ba -rich phase pre-calcinated BaO (with Ba-rich addition Ba-Cu-O Sm210 2 Sm211) Sm242 ( our lab) compound Ba mol% Addition amount 40 mol% 2-4 wt% 5 mol% 10 mol% 15 mol% 30 mol% =0.3302 Ba/Cu ratio in 0.755 0.8 0.72-0.75 0.71 0.75 0.79 0.89 precursor Tc(K) 90 89 93 94 94 93 <88 △Tc(K) 21.5151 3>10 the appropriate ratio of Ba:Cu ranges from 0.72 to 0.8 8 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. Effects of adding BaBa--richrich NdBa22 Cu Ba44 phase22 CuOO9 phase on airon air on--processed air NdBCO superconductor bulks Supercond. Sci. & Technol. 2014 Tc and Jc were effectively enhanced with increasing the Ba/Cu ratio (BCR) . Optimal properties were achieved when BCR reaches 0.80. 9 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. Trapping mode controlled continuous growth of SmBCO bulk Either self-nucleation or discontinuous BN Peng Cryst. Growth & Des. (2013) growth occurs in air-processed SmBCO Reduction of t.c.s value caused discontinuous growth t.c.s : tempera ture coe ffic ien t o f so lu bility 211 caused discontinuous growth Δc ⎛ ∂c ⎞ ΔT ⎛ ∂c ⎞ J = = ⎜ ⎟ ⋅ = ⎜ ⎟ ⋅ R Δt ⎝ ∂ ⎠T ΔtT ⎝ ∂T ⎠T R=constant in a normal cooling process ⎛ ∂c ⎞ ⎜ ⎟ didereasing shlharply in Sm BCOsystem ⎝ ∂T ⎠T i.e. noticeable reduction of t.c.s with decreasing temperature !!! 211 coarsening/ Reduction in effective Growth slows down Reduction in 211 segregation supersaturation and terminates J (solute flux) 10 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. Δc ⎛ ∂c ⎞ ΔT ⎛ ∂c ⎞ J= =⎜ ⎟⋅ =⎜ ⎟ ⋅ R Accelerated cooling rate at a proper time Δt ⎝ ∂T ⎠T Δt ⎝ ∂T ⎠T ⎛ ∂c ⎞ ⎜ ⎟ sharplydereasing in systemSmBCO ⎝ ∂T ⎠T BN Peng Cryst. Growth & Des. (2013) 211 Coarsening and Growth segggregation are continues partially suppressed Optimized profile for continuous growth of SmBCO bulks 11 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. Potential of LREBCO (LRE=(LRE=Nd,SmNd,Sm..) bulks..) bulks • Advantages compared to YBCO: ※ Exhibit better superconductivity High Tcc High T High J Highcc at a highJ applied magnetic field ※ Higher growth rate due to high RE solubility in solvent • Problems to be solved : ※ Formation of solid solution (LRE1+xBa2-xCu3Oy) due to LRE/Ba substitution, leading to low Tc 9※ LkfLack oitf su blitabl ite blsee dd d GtiblkdGenetic bulk seed ; REBCO film seed 12 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. Our review paper on Prog.Prog. in Mater. Sci. 68 (2015) 97--159159159 (IF= 27 . 42） 13 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. Amazing superheating phenomenon Low Peritectic Temperature (1010ºC) YBCO Thin-film Seeding at High Processing Temperature (~1057ºC) Growing NdBCO Thick-films 14 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. • 20x20 mm2 ihin the a-blb plane. • ~ 010.1mm in the c-axis. • Growth rate ~ 10μm/min. •• YBCO thin film seed. •• Growth temperature=1057 ºC 15 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. InIn--situsitu observation of the YBCO melting 1010ºC Room temperature 3min J. Phys.: Condens. Matter (2003) 1050ºC 3min 1060ºC 3min 1) YBCO thin film can superheat about 50K; 2)orientation relationship:<001>(100)Y211∥<110>(001)MgO 16 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. Universal superheating of thin films & Wide feasibility in seeding the growth of REBCO 1.Using YBCO film-seed, LPE growth was succeeddided in various REBCO ox ides 2.REBCO film-seeds were extended in various growth processes including TSMG 3.Various REBCO films universally possess high thermal stability in TSMG 4.YBCO films on various substrates 17 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. UsinUsinggg YBCO fffilmilm--seedseed, LPE gggrowth was succeeded in various REBCO oxides RE123 systems Mixed RE123 systems NdBCO NiNi--( 1057ºC) NdBCO(~1057ºC) ( 1057ºC) NdBCO(~1057ºC) NdBCO (~1057ºC)-Sr (~1057ºC)-NdBCONdBCO Sr (~1057ºC) NdYBCO Nd-- YBCO(1000~ 1030ºC) SmBCO SmBCO YbYb--YBCOYBCO (970~980ºC) (1020~ 1055ºC) CaCa--YBCOYBCO (957~980ºC) ZnZn--YBCOYBCO (966~984ºC) 18 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015. REREBCOBCO filmfilm--seedsseeds were extended in variiious growththth processes Top-•• -SeededSeeded Top Solution-Solution-GrowthGrowthTSSG ( TSSG)) --SinSingle crystal. Top-•• -SeededSeeded Top Melt--GrowthGrowth (TSMG) --sinsingle domain bulkc 211 + melt •• Liquid phase epitaxy growthLPE ( LPE)) hit k--t filhick fil him m k fil 19 IEEE/CSC & ESAS SUPERCONDUCTIVITY NEWS FORUM (global edition), April 2016. Invited presentation PC-1-INV given at ISS 2015 in Funabori, Tokyo, Japan, November 16 to 18th, 2015.
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