The effect of electron doping on the structural, transport, and magnetic properties of Mn (IV) - rich Ca1-xYxMnO3 (x < 0.2) samples have been investigated using neutron diffraction, neutron depolarization, magnetization and resistivity techniques. The temperature dependence of resistivity follows the small polaron model and the activation energy exhibits a minimum for x=0.1 sample. A phase separated magnetic ground state consisting of ferromagnetic domains (~7microns) embedded in G-type antiferromagnetic matrix is observed in the sample, x = 0.1. The transition to the long range magnetically ordered state in this sample is preceded by a Griffiths phase. On lowering temperature below 300K a structural transition from orthorhombic structure (Pnma) to a monoclinic structure (P21/m) is observed in the case of x=0.2 sample. The ferromagnetic behavior in this case is suppressed and the antiferromagnetic ordering is described by coexisting C-type and G-type magnetic structures corresponding to the monoclinic and orthorhombic phases, respectively.<
An integrated approach to doped thin films with strain tunable magnetic anisotropy: Powder synthesis, target preparation and pulsed laser deposition of Bi:YIG
The spin-state crossover and low-temperature magnetic state in yttrium doped Pr$_{0.7}$Ca$_{0.3}$CoO$_3$
研究了两种混合价钴酸盐的结构和磁性,每f.u.含0.30个Co $^{4+}$离子,(Pr用高分辨中子衍射、SQUID磁强计和热容测量方法研究了$_{1-y}$ Y $_{y}$)$_{0.7}$ Ca $_{0.3}$ CoO $_3$($y=0$和0.15)的低温结构。结果被解释的自旋状态的交叉从室温下的混合物的中间自旋Co $^{3+}$和低自旋Co $^{4+}$(IS/LS)在样品基态的LS/LS混合物的情况下。与不含钇的$y=0$相比,掺杂体系$y=0.15$在132 K时发生了一阶金属-绝缘体转变,在此过程中不仅发生了向低自旋态的跃迁,而且还发生了部分电子从Pr $^{3+}$ 4f向钴3d态的转移.考虑到LS Co $^{3+}$的非磁性特征,这种价移电子跃迁导致磁稀释,形式上为0.12 LS Co $^{4+}$或0.12 $t_{2g}$空穴自旋/f.u.,这是没有长程有序的绝缘的、高度不均匀的磁基态的原因。然而,即使在这种情况下,也存在分布在整个晶格上的相对较强的分子场。认为$y=0$中自发的FM阶和$y=0.15$中强FM相关的存在显然与LS/LS相位的单$t_{2g}$带特征相矛盾。我们建议的解释依赖于一个模型的缺陷诱导,巡回孔介导的磁性,其中的缺陷被确定与磁性高自旋Co PDMATHAMT物种稳定附近的氧空位。
Single-pulse strain-induced precessional dynamics of magnetization in Co-doped iron garnet
HFML-FELIX;Radboud University, Institute for Molecules and Materials(拉德堡德大学分子与材料研究所);Russian Quantum Center, Skolkovo Innovation Center(俄罗斯量子中心斯科尔科沃创新中心);Faculty of Physics, Lomonosov Moscow State University(莫斯科国立大学物理系);Faculty of Physics, University of Bialytsok(比亚韦斯托克大学物理系)
Study on the hydrogen behavior in Y and Co doped barium-zirconate
采用热脱附谱(TDS)研究了混合钙钛矿氧化物、钇钴掺杂锆酸钡(BaZr $_{0.955}$ Y $_{0.03}$ Co $_{0.015}$ O $_{3-a}$(BZYC))在D $_2$和D $_2$ O气氛中的氢释放行为.氢的释放出现在1000 K左右。氢溶解度在暴露于D $_2$ O的BZYC样品中较高。
Compound-tunable embedding potential method to model local electronic excitations on $f$-element ions in solids: Pilot relativistic coupled cluster study of Ce and Th impurities in yttrium orthophosphate, YPO$_4$
Use of local density approximation within range separated hybrid exchange-correlation functional to investigate Pb doped SnO$_2$ as an electron transport layer
Electronic and magnetic properties of V-doped anatase TiO$_{2}$ from first principles
采用第一性原理研究了钒掺杂的二氧化钛$_{2}$的几何、电子和磁性。DFT+U(Hubbard系数)方法预测了Ti $_{1-x}$ V $_{x}$ O $_{2}$(x=6.25和12.5%)的半导体能带结构,与样品的低电导率很好地吻合,而广义梯度近似内的标准计算失败。理论结果表明,钒原子倾向于保持接近,并通过超交换相互作用产生强铁磁性。氧空位诱导的磁极化子能使大范围分离的磁性杂质之间产生长程铁磁相互作用。实验观察到的室温下V掺杂的TiO_2 $_{2}$的铁磁性可能源于短程超交换耦合和长程束缚磁极化子逾渗的结合。
Site-Selective Yttrium Substitution in Ti3AlC2 Enables Interlayer Engineering and Li Transport in Ti3C2Tx cathodes for High-Power Energy Storage
ICMUV, Instituto de Ciencia de Materiales, Universidad de Valencia(瓦伦西亚大学材料科学研究所);King Danylo University(丹尼洛国王大学);Department of Applied Physics and Electromagnetism, University of Valencia(瓦伦西亚大学应用物理与电磁学系)
Poisoning of magnetism in silicon doped with Re, caused by a charge transfer from interstitials to substitutionals, by means of the self-interaction corrected density-functional approach
On the microscopic origin of the magneto-electronic phase separation in Sr doped LaCoO3
用局域探针研究了掺杂La_(1-x)Sr_xCoO_3钙钛矿的纳米磁电子相分离。相分离是直接观察到的穆斯堡尔谱在所研究的掺杂范围为0.05 <= x <= 0.25在室温下,以及在低温磁相。扩展与当前的同步加速器为基础的X射线光谱,这些数据有助于表征的体积以及不同阶段的局部电和磁性能。基于掺杂Sr离子的随机分布的简单模型很好地描述了分离相的演化以及Co自旋态的变化。实验表明,Sr掺杂引发小液滴和高度掺杂驱动的钴自旋态转变,而无Sr的第二相随着Sr含量的增加而迅速消失。