Vortex liquid entanglement in twinned YBa 2 Cu 3 O 7 / Y 2 BaCuO 5 composite superconductors
Vortex liquid entanglement in twinned YBa 2 Cu 3 O 7 / Y 2 BaCuO 5 composite superconductors
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孪晶YBa 2 Cu 3 O 7 / Y 2 BaCuO 5 复合超导体中的涡流液体缠结
DOI：
10.1103/physrevb.60.13099
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发表时间：
1999
影响因子：
3.7
通讯作者：
X. Obradors
中科院分区：
文献类型：
--
作者：
T. Puig;F. Galante;E. González;J. Vicent;B. Martínez;X. Obradors
测量了YBa_2Cu_3O_7/Y_2BaCuO_5熔体织构复合材料的面内电阻率ρ（T，H，θ）随磁场和温度的变化关系，用各向异性Ginzburg-Landau方法验证了超导态的本征各向异性。分析了Y_2BaCuO_5沉淀物产生的孪晶界和淬火无序等相关缺陷对复合材料在液涡态下钉扎行为的影响，测定了相应的相图，并与孪晶单晶的相图进行了比较。我们发现，不可逆线显示向上移动，由于孪晶界钉扎，使定义一个“淬火”玻色玻璃化转变。一个新的区域中的涡旋液体状态的双边界钉扎定义了一个部分纠缠的液体涡旋状态，其特征在于由短程c轴涡相干。实验确定了到纠缠液相的过渡。这种脱钉线的相关性和它的独特的位置相对于孪生单晶进行了讨论。[S0163- 1829（99）01741-5]。
The angular dependence of the in-plane resistivity ρ(T,H, θ) of melt textured YBa_2Cu_3O_7/Y_2BaCuO_5 composites has been measured in a large range of magnetic fields and temperatures and from them, the intrinsic anisotropy of the superconducting state has been verified following the anisotropic Ginzburg-Landau approach. The influence of correlated defects like twin boundaries and quenched disorder generated by Y_2BaCuO_5 precipitates on the pinning behavior of these composites in the liquid vortex state is analyzed, and the corresponding phase diagram is determined and compared to that of twinned single crystals. We show that the irreversibility line displays an upwards shift due to twin boundary pinning enabling to define a ''quenched'' Bose glass transition. A new region in the vortex liquid state is identified where twin boundary pinning defines a partially entangled liquid vortex state characterized by a short-range c-axis vortex coherence. The transition to the entangled liquid phase is experimentally determined. The relevance of this depinning line and its unique position with respect to twinned single crystals is discussed. [S0163- 1829(99)01741-5].