Budget Amount *help |
¥4,900,000 (Direct Cost: ¥4,900,000)
Fiscal Year 1989: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1988: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1987: ¥3,300,000 (Direct Cost: ¥3,300,000)
|
Research Abstract |
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.
|