Fermi Surface Study of Rare Earth Compounds due to the de Haas-van Alphen effect

稀土金属间化合物表现出多种磁性能，如定域f电子、价涨落、密集近藤和重电子等，这些磁性能是基于导电电子和f电子的杂化程度。在本研究项目中，我们测定了稀土化合物的费米表面和回旋质量。首先，我们构建了^ 3he系统，结合16-T超导磁体来测量de Haas-van。α (dHvA)振荡与磁阻。一年半过去了。在样品空间上进行了特殊设计，采用玻璃环氧（非金属）g10材料，而不是不锈钢材料，以减少100 Oe左右调制场产生的热加热。dHvA振荡检测系统的灵敏度也提高了10-100倍。提高了单晶的质量；CeCu_2、CeSn_3、CeIn_3、CeGa_2等重电子化合物的残余电阻率很小，只有0.1 ~ 0.5 cm。我们相信这是世界上最好的样品。我们测定了CeB_6， PrB_6, CeCu_2, YCu_2, CeNi, LaNi， CeSn_3和LaSn_3， CeIn_3和NdCu_6的费米表面和回旋加速器质量。其中，我们与富山大学的K. Sato教授和布里斯托尔大学的M. Springford教授进行了合作。CeB_6、PrB_6、CeNi CeIn_3和NdCu_6的费米表面与相应的la -化合物相似，而CeCu_2和CeSn_3的费米表面与相应的la -化合物不同。

The rare earth intermetallic compounds demonstrate variety of magnetic properties such as localized f-electron, valence fluctuation, dense Kondo and heavy electron, which are based on the degree of hybridization between conduction electrons and f-electrons. In this research project we have determined the Fermi surface and cyclotron mass of rare earth compounds. First we have constructed the ^3He-system, combined with the 16-T superconducting magnets to measure the de Haas-van. Alphen (dHvA) oscillation and the magnetoresistance. One year and half has passed to complete it. Special design was introduced on the sample space, not made of stainless steel but of glass-epozy(non-metallic) G 10 material to reduce the thermal heating due to the modulation field of about 100 Oe. Sensitivity of the detecting system of the dHvA oscillation was also improved, 10-100 times than the previous system. Moreover, quality of single crystals was improved; the residual resistivity of heavy electron compounds such as CeCu_2, CeSn_3, CeIn_3, and CeGa_2, became so small, 0.1-0.5 .cm. We believe these are the best sample in the world. We have determined the Fermi surfaces and cyclotron masses of CeB_6, PrB_6, CeCu_2, YCu_2, CeNi, LaNi, CeSn_3 and LaSn_3, CeIn_3 an NdCu_6. Among them we have done the cooperative works with Prof. K. Sato, Toyama University and also with Prof. M. Springford, University of Bristol. Fermi surfaces of CeB_6, PrB_6, CeNi CeIn_3 and NdCu_6 are concluded to be similar to those of the corresponding La-compounds, while those of CeCu_2 and CeSn_3 are different from the corresponding La-compounds.