The Experts below are selected from a list of 105 Experts worldwide ranked by ideXlab platform
Y Shiokawa - One of the best experts on this subject based on the ideXlab platform.
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spin glass behavior in cecu2 type Uranium Compound u2auga3
Applied Physics Letters, 2005Co-Authors: D X Li, Tomoo Yamamura, Kunio Yubuta, Shigeki Nimori, Y ShiokawaAbstract:We present the results of ac and dc susceptibility, magnetization, magnetic relaxation, specific heat, and electrical resistivity measurements on U2AuGa3, an orthorhombic CeCu2-type nonmagnetic atom disorder system. These data clearly indicate that U2AuGa3 undergoes a spin glass phase transition at a static freezing temperature Ts=23.6K, in spite of the lack of triangular magnetic structure. It is observed that the variation of the characteristic temperature Tir (the bifurcation point between field-cooled and zero-field-cooled susceptibilities) with applied field H for U2AuGa3 is not consistent with the “AT line,” but follows a Tir∝−H2∕5 law. The observed spin glass behavior and the formation of frustrated magnetic interactions in U2AuGa3 are discussed in a magnetic cluster model.
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spin glass behavior in ternary Uranium Compound u2cuga3
Journal of Alloys and Compounds, 2004Co-Authors: Tomoo Yamamura, D X Li, Kunio Yubuta, Y ShiokawaAbstract:Abstract The results of dc susceptibility, magnetization, magnetic relaxation and specific heat measurements on U 2 CuGa 3 , a Compound reported early in the literature as exhibiting interesting magnetic properties, are presented. The temperature dependence of susceptibility measured in the zero-field cooling (ZFC) mode and in the field cooling (FC) mode displays spin-glass behavior below a characteristic temperature T f (∼16 K) in agreement with the literature. As a new evidence for the formation of spin-glass state in this Compound, the specific heat data do not show any visible singularity around T f indicating the absence of long-range magnetic order at this temperature. Furthermore, the characteristic remanence effect and magnetic relaxation on a macroscopic time scale are also observed below T f . The experimental results are compared with those of orthorhombic CeCu 2 -type spin-glass Compound U 2 AuGa 3 and hexagonal AlB 2 -type spin-glass Compound U 2 PdSi 3 .
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spin glass like behavior of ternary Uranium Compound u2ausi3
Solid State Communications, 1998Co-Authors: Dexin Li, Y Shiokawa, A Kimura, Y Homma, A Uesawa, Takashi SuzukiAbstract:Abstract DC magnetization, specific heat and magnetic relaxation measurements are reported for a polycrystalline U2AuSi3. The temperature dependence of the magnetization shows a cusp at a characteristic temperature Tf that strongly depends on the applied magnetic field. The specific heat does not show visible singularity around Tf, ruling out the existence of the usual long range spatial magnetic order. The pronounced difference between the zero field cooled (ZFC) and the field cooled (FC) magnetization, as well as the very slow decay of the remanence indicate the occurrence of a highly irreversible frozen state below Tf. These features are the characteristics of spin glass behavior.
D.a. Milliken - One of the best experts on this subject based on the ideXlab platform.
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Microstructural variations with Uranium Compound doping of Bi-Sr-Ca-Cu-O/Ag superconducting tapes
IEEE Transactions on Applied Superconductivity, 2001Co-Authors: D.a. MillikenAbstract:Doping of Bi-Sr-Ca-Cu-O based silver sheathed superconducting tapes (BSCCO/Ag) with various Uranium Compounds was carried out. This work was aimed at minimising the detrimental effects of doping to allow for later irradiation and fission to create columnar defects for strong flux pinning. The effects on the transport current density of BSCCO/Ag of doping with a variety of Uranium Compounds up to 2 at% was determined. Microstructural changes due to the doping were investigated. Removal of elements from the BSCCO matrix by Uranium Compound dopants was studied by energy dispersive spectroscopy. It was found that UCa/sub 1.5/Sr/sub 1.5/O/sub 6/ least degraded electrical performance and microstructure, as it removed the least elements from the matrix. It would appear that UCa/sub 1.5/Sr/sub 1.5/O/sub 6/ most closely approximates an ideal BSCCO compatible Uranium Compound, but it still removes some amount of copper.
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chemistry of Uranium Compound doping in bi pb 2sr2ca2cu3ox silver superconducting tapes
Physica C-superconductivity and Its Applications, 2000Co-Authors: D.a. MillikenAbstract:Abstract Equilibrium stable Compounds U(Ca,Sr) 2 O 5 and U(Ca,Sr) 3 O 6 , have been identified in the U Bi Sr Ca Cu O system. These Compounds have been synthesised and added to Bi-2223/Ag composite tapes in progressively greater amounts. Bi-2223/Ag doped with these Compounds using compositions closer to the equilibrium composition has been shown to have superior superconducting properties to that doped with Uranium oxide Compounds. The effects of chemical degradation by Uranium Compound dopants via Strontium and Calcium removal from the Bi-2223 structure have been indirectly determined by I c measurements. Losses in I c can be minimised by stabilising Uranium into appropriate Compounds.
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Chemistry of Uranium Compound doping in (Bi, Pb)2Sr2Ca2Cu3Ox/silver superconducting tapes
Physica C-superconductivity and Its Applications, 2000Co-Authors: D.a. MillikenAbstract:Abstract Equilibrium stable Compounds U(Ca,Sr) 2 O 5 and U(Ca,Sr) 3 O 6 , have been identified in the U Bi Sr Ca Cu O system. These Compounds have been synthesised and added to Bi-2223/Ag composite tapes in progressively greater amounts. Bi-2223/Ag doped with these Compounds using compositions closer to the equilibrium composition has been shown to have superior superconducting properties to that doped with Uranium oxide Compounds. The effects of chemical degradation by Uranium Compound dopants via Strontium and Calcium removal from the Bi-2223 structure have been indirectly determined by I c measurements. Losses in I c can be minimised by stabilising Uranium into appropriate Compounds.
Tomoo Yamamura - One of the best experts on this subject based on the ideXlab platform.
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spin glass behavior in cecu2 type Uranium Compound u2auga3
Applied Physics Letters, 2005Co-Authors: D X Li, Tomoo Yamamura, Kunio Yubuta, Shigeki Nimori, Y ShiokawaAbstract:We present the results of ac and dc susceptibility, magnetization, magnetic relaxation, specific heat, and electrical resistivity measurements on U2AuGa3, an orthorhombic CeCu2-type nonmagnetic atom disorder system. These data clearly indicate that U2AuGa3 undergoes a spin glass phase transition at a static freezing temperature Ts=23.6K, in spite of the lack of triangular magnetic structure. It is observed that the variation of the characteristic temperature Tir (the bifurcation point between field-cooled and zero-field-cooled susceptibilities) with applied field H for U2AuGa3 is not consistent with the “AT line,” but follows a Tir∝−H2∕5 law. The observed spin glass behavior and the formation of frustrated magnetic interactions in U2AuGa3 are discussed in a magnetic cluster model.
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spin glass behavior in ternary Uranium Compound u2cuga3
Journal of Alloys and Compounds, 2004Co-Authors: Tomoo Yamamura, D X Li, Kunio Yubuta, Y ShiokawaAbstract:Abstract The results of dc susceptibility, magnetization, magnetic relaxation and specific heat measurements on U 2 CuGa 3 , a Compound reported early in the literature as exhibiting interesting magnetic properties, are presented. The temperature dependence of susceptibility measured in the zero-field cooling (ZFC) mode and in the field cooling (FC) mode displays spin-glass behavior below a characteristic temperature T f (∼16 K) in agreement with the literature. As a new evidence for the formation of spin-glass state in this Compound, the specific heat data do not show any visible singularity around T f indicating the absence of long-range magnetic order at this temperature. Furthermore, the characteristic remanence effect and magnetic relaxation on a macroscopic time scale are also observed below T f . The experimental results are compared with those of orthorhombic CeCu 2 -type spin-glass Compound U 2 AuGa 3 and hexagonal AlB 2 -type spin-glass Compound U 2 PdSi 3 .
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spin glass behavior in ternary Uranium Compound u2auga3
Physica B-condensed Matter, 2003Co-Authors: Tomoo YamamuraAbstract:Abstract The magnetic properties of the intermetallic Compound U2AuGa3 were investigated on well-annealed polycrystalline samples by DC magnetization, specific heat and magnetic relaxation measurements. The temperature dependence of magnetization shows irreversibility and the frozen-in magnetic moment was observed below a characteristic temperature T f =23 K . The temperature dependence of the specific heat does not show any visible singularity indicating the absence of the long-range magnetic order around Tf. Furthermore, more than 50% of the remnant magnetization is observed even after 3 h due to the long-time magnetic relaxation effect. These results clearly indicate that U2AuGa3 undergoes the spin-glass transition at Tf.
D X Li - One of the best experts on this subject based on the ideXlab platform.
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spin glass behavior in cecu2 type Uranium Compound u2auga3
Applied Physics Letters, 2005Co-Authors: D X Li, Tomoo Yamamura, Kunio Yubuta, Shigeki Nimori, Y ShiokawaAbstract:We present the results of ac and dc susceptibility, magnetization, magnetic relaxation, specific heat, and electrical resistivity measurements on U2AuGa3, an orthorhombic CeCu2-type nonmagnetic atom disorder system. These data clearly indicate that U2AuGa3 undergoes a spin glass phase transition at a static freezing temperature Ts=23.6K, in spite of the lack of triangular magnetic structure. It is observed that the variation of the characteristic temperature Tir (the bifurcation point between field-cooled and zero-field-cooled susceptibilities) with applied field H for U2AuGa3 is not consistent with the “AT line,” but follows a Tir∝−H2∕5 law. The observed spin glass behavior and the formation of frustrated magnetic interactions in U2AuGa3 are discussed in a magnetic cluster model.
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spin glass behavior in ternary Uranium Compound u2cuga3
Journal of Alloys and Compounds, 2004Co-Authors: Tomoo Yamamura, D X Li, Kunio Yubuta, Y ShiokawaAbstract:Abstract The results of dc susceptibility, magnetization, magnetic relaxation and specific heat measurements on U 2 CuGa 3 , a Compound reported early in the literature as exhibiting interesting magnetic properties, are presented. The temperature dependence of susceptibility measured in the zero-field cooling (ZFC) mode and in the field cooling (FC) mode displays spin-glass behavior below a characteristic temperature T f (∼16 K) in agreement with the literature. As a new evidence for the formation of spin-glass state in this Compound, the specific heat data do not show any visible singularity around T f indicating the absence of long-range magnetic order at this temperature. Furthermore, the characteristic remanence effect and magnetic relaxation on a macroscopic time scale are also observed below T f . The experimental results are compared with those of orthorhombic CeCu 2 -type spin-glass Compound U 2 AuGa 3 and hexagonal AlB 2 -type spin-glass Compound U 2 PdSi 3 .
Kunio Yubuta - One of the best experts on this subject based on the ideXlab platform.
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spin glass behavior in cecu2 type Uranium Compound u2auga3
Applied Physics Letters, 2005Co-Authors: D X Li, Tomoo Yamamura, Kunio Yubuta, Shigeki Nimori, Y ShiokawaAbstract:We present the results of ac and dc susceptibility, magnetization, magnetic relaxation, specific heat, and electrical resistivity measurements on U2AuGa3, an orthorhombic CeCu2-type nonmagnetic atom disorder system. These data clearly indicate that U2AuGa3 undergoes a spin glass phase transition at a static freezing temperature Ts=23.6K, in spite of the lack of triangular magnetic structure. It is observed that the variation of the characteristic temperature Tir (the bifurcation point between field-cooled and zero-field-cooled susceptibilities) with applied field H for U2AuGa3 is not consistent with the “AT line,” but follows a Tir∝−H2∕5 law. The observed spin glass behavior and the formation of frustrated magnetic interactions in U2AuGa3 are discussed in a magnetic cluster model.
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spin glass behavior in ternary Uranium Compound u2cuga3
Journal of Alloys and Compounds, 2004Co-Authors: Tomoo Yamamura, D X Li, Kunio Yubuta, Y ShiokawaAbstract:Abstract The results of dc susceptibility, magnetization, magnetic relaxation and specific heat measurements on U 2 CuGa 3 , a Compound reported early in the literature as exhibiting interesting magnetic properties, are presented. The temperature dependence of susceptibility measured in the zero-field cooling (ZFC) mode and in the field cooling (FC) mode displays spin-glass behavior below a characteristic temperature T f (∼16 K) in agreement with the literature. As a new evidence for the formation of spin-glass state in this Compound, the specific heat data do not show any visible singularity around T f indicating the absence of long-range magnetic order at this temperature. Furthermore, the characteristic remanence effect and magnetic relaxation on a macroscopic time scale are also observed below T f . The experimental results are compared with those of orthorhombic CeCu 2 -type spin-glass Compound U 2 AuGa 3 and hexagonal AlB 2 -type spin-glass Compound U 2 PdSi 3 .
