arXiv subjects

Masahumi Kohgi

Publications and source records attributed to Masahumi Kohgi.

2 recordsLinked to original sources

arXiv2005

Evolution of 4f-Electron States in the Metal-Insulator Transition of PrRu$_4$P$_{12}$

Magnetic excitations of the filled skutterudite PrRu4P12 exhibiting a metal-insulator (M-I) transition at TM-I= 63 K were studied by inelastic neutron scattering experiment. The spectra at temperatures much lower than TM-I are described as well-defined crystal-field excitations. With approaching TM-I, the excitation peaks broaden and shift considerably together with the temperature variation of the carrier number and the atomic displacement in the transition. The 4f-electron state evolve from the well localized state in the insulator phase to the strongly hybridized itinerant state by p-f mixing near TM-I. The hybridization is responsible for the M-I transition of PrRu4P12.

cond-mat.str-el↗

arXiv2005

Role of p-f Hybridization in the Metal-Non-Metal Transition of PrRu4P12

Electronic state evolution in the metal-non-metal transition of PrRu4P12 has been studied by X-ray and polarized neutron diffraction experiments. It has been revealed that, in the low-temperature non-metallic phase, two inequivalent crystal-field (CF) schemes of Pr3+ 4f^2 electrons with Gamma_1 and Gamma_4^(2) ground states are located at Pr1 and Pr2 sites forming the bcc unit cell surrounded by the smaller and larger cubic Ru-ion sublattices, respectively. This modulated electronic state can be explained by the p-f hybridization mechanism taking two intermediate states of 4f^1 and 4f^3. The p-f hybridization effect plays an important role for the electronic energy gain in the metal-non-metal transition originated from the Fermi surface nesting.

cond-mat.str-el↗