论文标题
电子掺杂的库层超导体PR $ _ {0.87} $ lece $ _ {0.13} $ cuo $ _4 $
Vortex Dynamics and Phase Diagram in the Electron Doped Cuprate Superconductor Pr$_{0.87}$LaCe$_{0.13}$CuO$_4$
论文作者
论文摘要
已广泛探索了掺杂孔的丘陵和铁皮层超导体的第二磁化峰（SMP）。但是，在电子掺杂的铜层家族中的类似特征并不常见。在这里，我们在电子掺杂的Cuprate Pr $ _ {0.87} $ lace $ _ {0.13} $ CUO $ _4 $超导体使用DC磁化测量值的单晶中报告了涡流动力学研究。在等温$ m（H）$中的SMP功能以$ H $ \ Parallel $$ ab $ - planes观察到。另一方面，没有观察到$ H $$ \ Parallel $$ C $轴的晶体中的这种功能。使用磁性弛豫数据，通过集体蠕变理论对激活能量进行详细分析表明，在SMP上弹性到塑料蠕变跨界。此外，对于$ h $$ \并行$$ ab $，还观察到临界电流密度的温度依赖性在7 K附近，这可能与低温下约瑟夫森涡流的出现相关的维度跨界（3D-2D）有关。获得的各向异性参数获得了$γ$ $ \ $ 8-11表示涡旋晶格的3D性质主要是$ h $$ \ parallel $$ $$ c $轴。出现了$ h $ - $ t $的相图，$ h $$ \ parallel $$ c $和$ h $$ \ parallel $$ ab $。
Second magnetization peak (SMP) in hole-doped cuprates and iron pnictide superconductors has been widely explored. However, similar feature in the family of electron-doped cuprates is not common. Here, we report the vortex dynamics study in the single crystal of an electron-doped cuprate Pr$_{0.87}$LaCe$_{0.13}$CuO$_4$ superconductor using dc magnetization measurements. A SMP feature in the isothermal $M(H)$ was observed for $H$$\parallel$$ab$-planes. On the other hand, no such feature was observed for $H$$\parallel$$c$-axis in the crystal. Using magnetic relaxation data, a detailed analysis of activation pinning energy via collective creep theory suggests an elastic to plastic creep crossover across the SMP. Moreover, for $H$$\parallel$$ab$, a peak in the temperature dependence of critical current density is also observed near 7 K, which is likely be related to a dimensional crossover (3D-2D) associated to the emergence of Josephson vortices at low temperatures. The anisotropy parameter obtained $γ$ $\approx$ 8-11 indicates the 3D nature of vortex lattice mainly for $H$$\parallel$$c$-axis. The $H$-$T$ phase diagrams for $H$$\parallel$$c$ and $H$$\parallel$$ab$ are presented.
