The study of“irreversibility line”and magnetization curves of a YBCO superconductor prepared by melt-textured growth method is presented.It is shown'that the temperature T above whjich the magnetization is rever...The study of“irreversibility line”and magnetization curves of a YBCO superconductor prepared by melt-textured growth method is presented.It is shown'that the temperature T above whjich the magnetization is reversible can be identified with the temperature above which J_(c) is negligible,demonstrating the.Yeshurun and Malozemoff's theory about“irreversibility line”.展开更多
The structural,magnetic and superconducting properties of the Tl_(2)Ba_(2)(Ca_(1-x)Mg_(x))_(2)Cu_(3)O_(y)system with x=0,0.05,0.1,0.15,0.2,0.3,0.4,0.5 were studied.Replacement of calcium by magnesium depresses Tc from...The structural,magnetic and superconducting properties of the Tl_(2)Ba_(2)(Ca_(1-x)Mg_(x))_(2)Cu_(3)O_(y)system with x=0,0.05,0.1,0.15,0.2,0.3,0.4,0.5 were studied.Replacement of calcium by magnesium depresses Tc from 116.3K(x=0)to 93.3K(x=0.5).The critical current also decreases with increasing x.展开更多
The magnetization curves of EuBa_(2)Cu_(3)O_(y) crystal prepared by melt-textured growth method were measured from 1.5 to 87K up to field 7.5T for H||C and H⊥C.Peak effects were observed at 60,70 and 73K for H||C,and...The magnetization curves of EuBa_(2)Cu_(3)O_(y) crystal prepared by melt-textured growth method were measured from 1.5 to 87K up to field 7.5T for H||C and H⊥C.Peak effects were observed at 60,70 and 73K for H||C,and 70,73 and 77K for H⊥C.It is shown that the magnetic field Hp at which the magnetization or critical current reach their extremum is approximately independent of temperature lire and the peak erects observed can be explained by matching effects.展开更多
The high Tc superconductor LaBa_(2-x)Ca_(x)Cu_(3)O_(y) has been studied and the composition dependence of Tc examined For x=1,Tconset=94K,Tc^(R=0)=80K.The structure of this system was refined utilizing the X-ray powde...The high Tc superconductor LaBa_(2-x)Ca_(x)Cu_(3)O_(y) has been studied and the composition dependence of Tc examined For x=1,Tconset=94K,Tc^(R=0)=80K.The structure of this system was refined utilizing the X-ray powder diffraction data,and it was found that the material is isostructural with YBa_(2)Cu_(3)O_(y).展开更多
The structure,magnetic,and superconducting properties of the (Tl_(1-x)Al_(x))2Ba_(2)Ca_(2)Cu_(3)O_(y) with x=0.05,0.1,0.15,0.2 were studied.The T_(c)^(R=0) depends on whether the sample has a 222S phase structure or h...The structure,magnetic,and superconducting properties of the (Tl_(1-x)Al_(x))2Ba_(2)Ca_(2)Cu_(3)O_(y) with x=0.05,0.1,0.15,0.2 were studied.The T_(c)^(R=0) depends on whether the sample has a 222S phase structure or has a 2212 phase structure.The magnetic properties in low field were measured and discussed.展开更多
文摘The study of“irreversibility line”and magnetization curves of a YBCO superconductor prepared by melt-textured growth method is presented.It is shown'that the temperature T above whjich the magnetization is reversible can be identified with the temperature above which J_(c) is negligible,demonstrating the.Yeshurun and Malozemoff's theory about“irreversibility line”.
文摘The structural,magnetic and superconducting properties of the Tl_(2)Ba_(2)(Ca_(1-x)Mg_(x))_(2)Cu_(3)O_(y)system with x=0,0.05,0.1,0.15,0.2,0.3,0.4,0.5 were studied.Replacement of calcium by magnesium depresses Tc from 116.3K(x=0)to 93.3K(x=0.5).The critical current also decreases with increasing x.
文摘The magnetization curves of EuBa_(2)Cu_(3)O_(y) crystal prepared by melt-textured growth method were measured from 1.5 to 87K up to field 7.5T for H||C and H⊥C.Peak effects were observed at 60,70 and 73K for H||C,and 70,73 and 77K for H⊥C.It is shown that the magnetic field Hp at which the magnetization or critical current reach their extremum is approximately independent of temperature lire and the peak erects observed can be explained by matching effects.
文摘The high Tc superconductor LaBa_(2-x)Ca_(x)Cu_(3)O_(y) has been studied and the composition dependence of Tc examined For x=1,Tconset=94K,Tc^(R=0)=80K.The structure of this system was refined utilizing the X-ray powder diffraction data,and it was found that the material is isostructural with YBa_(2)Cu_(3)O_(y).
文摘The structure,magnetic,and superconducting properties of the (Tl_(1-x)Al_(x))2Ba_(2)Ca_(2)Cu_(3)O_(y) with x=0.05,0.1,0.15,0.2 were studied.The T_(c)^(R=0) depends on whether the sample has a 222S phase structure or has a 2212 phase structure.The magnetic properties in low field were measured and discussed.
