In this paper, we report the study of transport and magnetic properties of ytterbium hexaboride (YbB6) nanowires grown by a low trigger-temperature (200–240 °C) solid state method. The temperature dependence of resistivity shows that the YbB6 nanowire undergoes a semiconductor-insulator transition (SIT) below 20 K with an activation energy ΔE of 1 meV. The value of ρ at 2 K reaches 49 times the value
在本文中,我们报告了通过低触发温度(200–240°C)固态方法生长的六硼化y(YbB 6 )纳米线的传输和磁性能的研究。电阻率的温度依赖性表明,YbB 6纳米线在20 K以下经历了半导体-绝缘体跃迁(SIT),其活化能ΔE为1 meV。2 K时的ρ值达到300 K时的ρ值的49倍(ρ2 K / ρ300 K = 49)。观察到的非饱和磁阻(MR)与B 2具有线性关系。YbB 6中的异常电子传输纳米线可以通过X射线光电子能谱(XPS)和顺磁磁化作用支持的硼缺乏来解释Yb离子的混合价。
On the thermoelectric and magnetic properties, hardness, and crystal structure of the higher boride YbB66
作者:Philipp Sauerschnig、Kantaro Tsuchiya、Takaho Tanaka、Yuichi Michiue、Oksana Sologub、Shu Yin、Akira Yoshikawa、Toetsu Shishido、Takao Mori
DOI:10.1016/j.jallcom.2019.152182
日期:2020.1
previous report of SmB66, and significantly larger than previously reported for Y and Er phases of REB66. However, unlike SmB66, the effective magnetic moment suggests a trivalent state for Yb instead of mixed valence, which was determined by measuring the magnetic susceptibility from 2 to 300 K. The composition of YbB66 was indicated to be metal-rich, which actually may be the origin of the good performance
摘要 在这项工作中,我们报告了对 YbB66 作为潜在高温热电材料的研究结果。通过光浮区法生长了高质量的单晶。热电传输特性在 373-973 K 的温度范围内测量 YbB66 与一般的 REB66 化合物一样,是一种 p 型半导体,其电特性可以通过莫特的可变范围跳跃机制来描述。它显示了非常大的塞贝克系数,范围从 373 K 时的 588 μV K-1 到 973 K 时的 241 μV K-1,并且电阻率 ρ 从 9.4×10-1 Ω m 降低了近 4 个数量级到 2.4 × 10 −4 Ω 米。连同 2.6 W m-1 K-1 的低热导率,在 1000 K 附近确定了接近 0.1 的最大 ZT,并且有朝着更高温度急剧增加的趋势,这与 SmB66 的先前报告相似,并且明显大于先前报告的 REB66 的 Y 和 Er 相。然而,与 SmB66 不同的是,有效磁矩表明 Yb 为三价态而不是混合价,这是通过测量
their thermoelectricproperties. Single phase of orthorhombic AlMgB14, which contains B12 icosahedral clusters as building blocks, was obtained at sintering temperatures between 1573 and 1823 K. Seebeck coefficient (α) and electrical conductivity (σ) of the phase were about 500 μV/K and 10−1 1/Ω m at room temperature, respectively. These values are comparable to those of metal-dopedβ-rhombohedral boron
Abstract Single phase TmB12, YbB12 and LuB12 were successfully obtained by the arc-melting and floating zone methods. The XPS measurements of these compounds have indicated that (1) only YbB12 is a valence fluctuating compound with the valency of +2.9 at room temperature, (2) the correlation energy between Yb2+ and Yb3+ ions is about 6.0 eV, (3) Tm and Lu ions in the dodecaborides are in a trivalent state
11B nuclear quadrupole interaction in metal hexaborides (MB6)
作者:M. Aono、S. Kawai
DOI:10.1016/0022-3697(79)90033-7
日期:1979.1
and trivalent-metal hexaborides (MB 6 ) as well as in mixed-valent SmB 6 has been measured by the nuclear magnetic resonance method. In each group of divalent- and trivalent-metal hexaborides, ¦ eq ¦ decreases remarkably with increasing lattice parameter. At a given lattice parameter, ¦ eq ¦ for the trivalent-metal hexaborides is smaller than that for the divalent-metal hexaborides. The value of ¦ eq