Study of the Physical Properties of Narrow and Direct f band.

窄直接f带物理性质的研究。

• 批准号: 03640290
• 负责人: KASAYA Mitsuo
• 金额: $ 1.15万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03640290/
• 关键词: 4f band; Kondo Insulator; Valence Fluctuation; CeRh_3B_2; Ce_3Au_<3-x>Pt_xSb_4; Crystalline field; 線二色性; 価数揺動状態; fバンド; 近藤効果; 希土類化合物

As a two-years(1991-1992) project, the research of title "Study of the Physical Properties of Narrow and Direct f band" started. In 1991, we built up apparatus of specific-heat measurement by using the light-pulse method and then prepared single crystal to perform the study planned in 1992. On the other hand, within these two years, study of so-called f electron system make great progress, and it is now believed that the terminology "Valence Fluctuation" which reminds of dynamical properties is not appropriate expression not only for metallic but also for insulating valence fluctuation compounds. In other words, ground state of valence fluctuating regime which has been believed to belong to phenomena in narrow and direct f-band and was a main theme in this project can be fairly well described by normal band calculation. Needless to say, our studies on YbB_<12> and Ce_3(Au_<1-x>Pt_x)_3Sb_4 contribute much to this conclusion. On the basis of these background, new aspect of a question tha … More t whether or not the anomalous ferromagnetic valence fluctuating compound CeRh_3B_2 and UIr_3B_2 can also be explained by the band calculation arises. The results of our research are as follows.1) Valence fluctuating state of Ce_3(Au_<1-x>Pt_x)_3Sb_4... Pt substitution for Au decreases one electron, resulting in the shift of Ce valence from 3+ to 4+ and valence fluctuating state in Ce_3Pt_3Sb_4. In this process, semiconducting property persists. This implies that the energy gap arises from the band gap.2) Transport of YbB_<12> under high pressure... We have measured pressure dependencies of the lattice parameter and energy gap. We have found that relative shift of lattice parameter at which energy gap becomes zero is the same in YbB_<12> and SmB_6.3) Study of the giant crystalline field and ferromagnetism in CeRh_3B_2 via Soft-X-ray linear-dichroism.4) Study of the magnetic property in Fe-doped UIr_3B_2... 5d band of Ir are polarized by Fe-moment and then ferromagnetism is appeared via f-d hybridization. Less

作为一个为期两年（1991-1992）的项目，开始了题为“窄直f带物理性质研究”的研究。1991年，我们用光脉冲法建立了比热测量装置，并于1992年制备了单晶进行计划的研究。另一方面，这两年来，对所谓的f电子系统的研究取得了很大的进展，现在人们认为，“价涨落”一词使人想起动力学性质，不仅不适用于金属价涨落化合物，也不适用于绝缘价涨落化合物。换句话说，价态波动的基态被认为是属于窄和直接f波段的现象，是本项目的主要主题，可以很好地用常规波段计算来描述。不用说，我们对YbB_<12>和Ce_3(Au_<1-x>Pt_x)_3Sb_4的研究对这一结论有很大贡献。在此背景下，提出了一个新的问题，即异常铁磁价波动化合物CeRh_3B_2和UIr_3B_2是否也可以用能带计算来解释。我们的研究结果如下。1) Ce_3(Au_<1-x>Pt_x)_3Sb_4…Pt取代Au减少了一个电子，导致Ce_3Pt_3Sb_4中Ce的价态由3+向4+转变，形成价态波动。在这个过程中，半导体特性仍然存在。这意味着能隙是由带隙产生的。2)高压下YbB_<12>的输运…我们测量了晶格参数和能隙的压强依赖性。我们发现YbB_<12 bb_0和smb_3在能隙变为零时晶格参数的相对位移是相同的。4)掺铁UIr_3B_2的磁性能研究……Ir的5d波段被fe矩极化，然后通过f-d杂化出现铁磁性。少

项目成果

Kasaya: "Magnetic properties of the Dense Kondo compounds Cepdsn and YbNisn" J.Magn.Magn.Mat.104ー107. 665-667 (1992)

Kasaya：“致密近藤化合物 Cepdsn 和 YbNisn 的磁性”J.Magn.Magn.Mat.104-107 (1992)。

YAMAGUCHI: "Giant Crystal field and Ferromagnetism in the Kondo System CeRh_2B_2." Phys.Rev.B46. 9845-9848 (1992)

YAMAGUCHI：“近藤星系 CeRh_2B_2 中的巨型晶体场和铁磁性。”

IGA: "Transport Properties under High Pressure of the Dense Kondo Compounds CePdSn and YbB_<12>." Physica. (1993)

IGA：“致密近藤化合物 CePdSn 和 YbB_<12> 在高压下的输运特性。”

KASAYA: "Crossover from magnetic to nonmagnetic ground state in the Kondo alloy system Ce(Ni_<1-x>Pd_x)Sn." J.Phys.Soc.Jpn.60. 2542-2545 (1991)

KASAYA：“近藤合金系 Ce(Ni_<1-x>Pd_x)Sn 中从磁性基态到非磁性基态的转变。”

M. Kohgi et al: "Neutron scattering studies of CeTSn(T=Ni,Pd)" J. Magn. Magn. Mat.108. 187-189 (1992)

M. Kohgi 等人：“CeTSn(T=Ni,Pd) 的中子散射研究”J. Magn。