论文标题
$\mathrm{La}_{\mathrm{1-}x} \mathrm{Mn}_{\mathrm{1-}y} \mathrm{O}_{\mathrm{1\pm}δ}$ buffer layers on inclined substrate deposited MgO templates for coated conductors
$\mathrm{La}_{\mathrm{1-}x} \mathrm{Mn}_{\mathrm{1-}y} \mathrm{O}_{\mathrm{1\pm}δ}$ buffer layers on inclined substrate deposited MgO templates for coated conductors
论文作者
论文摘要
大多数基于离子光束辅助沉积模板的基于离子光束的涂层的超导通导体使用$ \ mathrm {lamno_3} $（LMO）膜作为终止缓冲层。相比之下，基于倾斜底物沉积（ISD）-MGO技术的涂层导体仍以同型（Homoepi）-MGO作为帽层生产。在这项工作中，我们报告了电子束物理蒸气沉积在ISD-MGO/HOMOEEPI-MGO上的LMO缓冲层沉积。对纹理LMO膜的生长参数进行了系统的研究，并针对随后存放的$ \ mathrm {dyba_2cu_3o} _ {\ mathrm {\ mathrm {7-} $（7--} $（dybco）的临界电流密度（$ j_ \ mathrm {c} $）进行了优化。 LMO薄膜在表面没有生长的情况下以高达$ 4 \，\ mathrm {Å/s} $的增长率获得。尽管形成了包含$ 59 \，\％$ la的非杂化LMO膜，但在低于$ 775^{\ circ} \ mathrm {c} $的底物温度下获得了单相胶片，并在氧气部分压力下，$ 4 \ times10^{ - times10^{ - 4} { - 4} { - 发现存放在LMO上的Dybco膜的$ J_ \ MATHRM {C} $的同质性区域被发现独立于LMO厚度，范围从$ 50 \，\ Mathrm {nm} $到$ 450 \，\ 450 \，\ Mathrm {Nm {Nm} $。 lmo上的dybco胶片达到$ j_ \ mathrm {c} = 0.83 \，\ mathrm {ma/cm^2} $ $ 77 \，\ \ m athrm {k} $在零应用字段中。该价值高达$ 30 \，\％$比直接在Homoepi-Mgo上生长的Dybco电影高。与homoepi-mgo上的dybco相比，LMO上的LMO增长参数和更高的$ J_ \ MATHRM {C} $相比，该材料可在基于ISD-MGO技术的制造涂层导体中使用该材料。
Most commercial high-temperature superconducting coated conductors based on ion beam assisted MgO deposited templates use $\mathrm{LaMnO_3}$ (LMO) films as the terminating buffer layer. In contrast, coated conductors based on inclined substrate deposition (ISD)-MgO technology are still produced with homoepitaxial (homoepi)-MgO as the cap layer. In this work we report on the deposition of LMO buffer layers on ISD-MgO/homoepi-MgO by electron beam physical vapor deposition. The growth parameters of textured LMO films were studied systematically and their properties were optimized regarding the critical current densitiy ($J_\mathrm{c}$) of the subsequently deposited $\mathrm{DyBa_2Cu_3O}_{\mathrm{7-}δ}$ (DyBCO) superconducting films. LMO films without outgrowths at the surface were obtained at growth rates of up to $4\,\mathrm{Å/s}$. Despite the formation of non-stoichiometric LMO films containing $59\,\%$ La, single-phase films were obtained at substrate temperatures below $775^{\circ}\mathrm{C}$ and at oxygen partial pressures of up to $4\times10^{-4}\,\mathrm{mbar}$ due to a large homogeneity region towards La. The $J_\mathrm{c}$ values of DyBCO films deposited on LMO were found to be independent of the LMO thickness in a range from $50\,\mathrm{nm}$ to $450\,\mathrm{nm}$. DyBCO films on LMO reach $J_\mathrm{c}=0.83\,\mathrm{MA/cm^2}$ at $77\,\mathrm{K}$ in zero applied field. This value is up to $30\,\%$ higher than those of DyBCO films grown directly on homoepi-MgO. The wide range of LMO growth parameters and higher $J_\mathrm{c}$ values of DyBCO on LMO compared to DyBCO on homoepi-MgO make this material attractive for its use in manufacturing coated conductors based on ISD-MgO technology.
