Study of exotic phenomena in the low-carrier strongly correlated systems

2 years of this project，total 13 domestic researchers went to institutions or international conferences in Poland，czech,Germany and France to perform collaboration works and also to present the研究结果。Total 7foreign researchers也被引入perform the joint works related with the present project。The main results of The project are as follows:(1)我们已revealed，from the study of magnetic form factor of CeP by polarized neutron diffraction techniquethe unusual properties of CeP are due to the strong -f mixing effect which pulls theΓ D28 -type crystal field excited state down below the Γ D27 -type crystal field groundIt was also revealed the CeAs exhibits quite similar magnetic phase diagram under highpressure above abou 0.3 GPa. In order to investigate the effect of the unusual magnetic propertiesto the crystal lattice of Ce-monopnictides we have measured the phonon excitations in CeSb byinelastic neutron scatterin…more g,and found that a branch of unusual excitations is appears at the temperatures below Neel(2) We have revealed, by neutron inelastic scattering，that the heavy electron anomalies of Yb D24 D2As D23 d2r ascribed to the spin excitations inthe one-dimensional chains of Yb D13 D13 + ions which is caused by the charge ordering. the chargeordering was confirmed to be rather perfect from the polarized neutron experiment. the inelasticneutron scattering studies under magnetic field revealed the opening of energy gap in the spinexcitation spectra,which indicates the existence of a new correction term in the Heisenberg-type effective Hamiltonianof the charge ordered state of Yb - D24 - D2As - D23 - D2. the charge ordering phenomena of the similarmaterial Sm - D24 - D2Bi - D23 - D2 was also observed polarized neutron diffraction experiment.(3)The quadrupolar ordering and diminishing process of The ferromagnetism under high pressure of TmTewere studied by neutron diffraction experiment.(4) The heavy electron anomalies and valencefluctuation phenomena of Sm - D23 - D2Te - D24 - D2 were studied by inelastic neutron and polarizedneutron scattering.(5) Strong magnetic anisotropy and metamagnetic properties of UNiGa and UCoAl andalso the unusual properties of the skutterudite compound Rfe D24 D2P D212 d2d2 were studied bymacroscopic measurements such as the de Haas van Alphen measurement. Less

During 2 years of this project, total 13 domestic researchers were sent to institutions or international conferences in Poland, Czech, Germany and France to perform collaboration works and also to present the research results. Total 7 foreign researchers were also invited to perform the joint works related with the present project. The main results of the project are as follows :(1) We have revealed, from the study of magnetic form factor of CeP by polarized neutron diffraction technique, that the unusual properties of CeP are due to the strong p-f mixing effect which pulls the ΓィイD28ィエD2-type crystal field excited state down below the ΓィイD27ィエD2-type crystal field ground state. It was also revealed that the CeAs exhibits quite similar magnetic phase diagram under high pressure above abou 0.3 GPa. In order to investigate the effect of the unusual magnetic properties to the crystal lattice of Ce-monopnictides we have measured the phonon excitations in CeSb by inelastic neutron scatterin … More g, and found that a branch of unusual excitations is appears at the temperatures below Neel temperature.(2) We have revealed, by neutron inelastic scattering, that the heavy electron anomalies of YbィイD24ィエD2AsィイD23ィエD2 a r ascribed to the spin excitations in the one-dimensional chains of YbィイD13ィエD1+ ions which is caused by the charge ordering. The charge ordering was confirmed to be rather perfect from the polarized neutron experiment. The inelastic neutron scattering studies under magnetic field revealed the opening of energy gap in the spin excitation spectra, which indicates the existence of a new correction term in the Heisenberg-type effective Hamiltonian of the charge ordered state of YbィイD24ィエD2AsィイD23ィエD2. The charge ordering phenomena of the similar material SmィイD24ィエD2BiィイD23ィエD2 was also observed by polarized neutron diffraction experiment.(3) The quadrupolar ordering and diminishing process of the ferromagnetism under high pressure of TmTe were studied by neutron diffraction experiment.(4) The heavy electron anomalies and valence fluctuation phenomena of SmィイD23ィエD2TeィイD24ィエD2 were studied by inelastic neutron and polarized neutron scattering.(5) Strong magnetic anisotropy and metamagnetic properties of UNiGa and UCoAl and also the unusual properties of the skutterudite compound RfeィイD24ィエD2PィイD212ィエD2 were studied by macroscopic measurements such as the de Haas van Alphen measurement. Less