Joint Research For Acoustic Phonon Spectroscopy and Electron-Lattice Interraction

超声、布里渊散射和热体积效应的声谱仪是研究重费米子材料、高Tc化合物、低维系统等强关联系统的重要探针。具有轨道角自由度的量子系统的四极效应是本课题的重点。本文用超声测量方法研究了许多4f电子系统由于四极-应变相互作用而产生的四极极化率。本文从实验和理论两个方面研究了近藤化合物CeB 6、Ce 3 Pd 20 Ge 6和半导体TmTe中反铁型四极有序的特征性质。本文还通过低温超声测量研究了CexLa_（1-x）B_6体系中近藤耦合与四极有序的相互作用。通过费米表面的电子态来考察稀土单晶的声学德哈斯效应。在低载流子体系中，电子耦合对体应变的增强作用。CeRu_2中横模C_2的弹性软化<44>以及与超导特性的相互作用是有趣的结果。本项目主要研究了Yb ~（4+）As ~（3+）的电荷有序性、弹性软模、一维Yb ~（3+）离子的磁激发等问题，研讨会于1996年3月1-2- 3日在日本仙台Akyuu举行，1996年11月29-30日和12月1日在日本新泻Urasa举行。许多有趣的和重要的结果的介绍，这确实是宝贵的合作研究的参与者。

The acoustic spectroscopes of ultrasonic, Brillouin scattering and thermal volume effect are important probes to examine the strongly correlated systems of heavy fermion materials, high Tc compounds, low dimensional systems. The quadrupolar effect of the quantum system with orbital angular freedom is the most important subject of this project. The quadrupolar susceptibility due to the quadrupole-strain interaction of many 4f-electron systems were investigated by the ultrasonic measurements. The characteristic properties of the quadrupolar ordering with antiferro-type configuration in the Kondo compounds CeB6, Ce3Pd20Ge6, and semiconductor Tm Te were investigate by both experimental and theoretical approaches. The interplay of the Kondo coupling to the quadrupolar ordering in the Kondo system CexLa1-xB6 was also investigate low temperature ultrasonic measurements. The acoustic de Haas effect on rare earth monopunictides was performed to examined by the electronic states on the Fermi surfaces. The enhancement of the electron coupling to the volume strain in the low carrier systems was obtained. The elastic softening of transverse mode C_<44> in CeRu2 and interplay to the characteristic feature of the superconducting were interesting results. The charge ordering of the valence fluctuating compounds Yb4As3, the elastic soft mode, magnetic excitations Yb^<3+> ions with one dimensional character were progress in this project.The workshops of this project were hold as, (1) March 1-2-3,1996, Akyuu, Sendai, (2) November 29-30, December 1,1996, Urasa, Niigta. The presentations on many interesting and important resusts It were valuable indeed for cooperative researchs of participants.