Satoru Kunii

Spin-split fermi surfaces in CexLa1-xB6CexLa1-xB6 and PrxLa1-xB6PrxLa1-xB6

We have performed the dHvA measurements on CexLa1-xB6CexLa1-xB6 and PrxLa1-xB6PrxLa1-xB6 compounds to study spin splitting of the Fermi surfaces. In PrB66 we have found new frequency branches to confirm that the Fermi surface splits into up and down spin Fermi surfaces, whereas no spin splitting has been found for x=0.25,0.5,0.75x=0.25,0.5,0.75. We have also found several new frequency branches in CeB6CeB6. The new frequency branches imply that the Fermi surfaces of up and down spin conduction electrons are significantly different in CeB6CeB6 as well as in PrB6PrB6.

Effect of pressure and magnetic field on the electrical resistivity of TbB6

Electrical resistivity of a single crystal of TbB6 was studied under hydrostatic pressures up to 2.1 GPa and magnetic fields up to 9 T. The Neel temperature, rN, decreases linearly with increasing pressure: dlnTN/dP = 3.14×10-2 GPa-1 at zero external field. This pressure dependence of TN weakens as external fields increase. At ambient pressure, the magnetoresistance at 4.2 K is positive up to 4.8 T and becomes negative above 4.8 T. The positive magnetoresistance observed at ambient pressure is suppressed by applying pressure, which enhances the negative magnetoresistance. These results are interpreted in terms of the reduction of the scattering of conduction electrons, due to disordered magnetic moment being suppressed by derealization of 4f electrons at high pressure, and the magnetic field variation of the large transition probability between the ground state and the excited levels.

Spin-split fermi surfaces in CexLa1-xB6 and PrxLa1-xB6

We have performed the dHvA measurements on CexLa1-xB6CexLa1-xB6 and PrxLa1-xB6PrxLa1-xB6 compounds to study spin splitting of the Fermi surfaces. In PrB66 we have found new frequency branches to confirm that the Fermi surface splits into up and down spin Fermi surfaces, whereas no spin splitting has been found for x=0.25,0.5,0.75x=0.25,0.5,0.75. We have also found several new frequency branches in CeB6CeB6. The new frequency branches imply that the Fermi surfaces of up and down spin conduction electrons are significantly different in CeB6CeB6 as well as in PrB6PrB6.

Spin-split fermi surfaces in and

We have performed the dHvA measurements on CexLa1-xB6CexLa1-xB6 and PrxLa1-xB6PrxLa1-xB6 compounds to study spin splitting of the Fermi surfaces. In PrB66 we have found new frequency branches to confirm that the Fermi surface splits into up and down spin Fermi surfaces, whereas no spin splitting has been found for x=0.25,0.5,0.75x=0.25,0.5,0.75. We have also found several new frequency branches in CeB6CeB6. The new frequency branches imply that the Fermi surfaces of up and down spin conduction electrons are significantly different in CeB6CeB6 as well as in PrB6PrB6.

Non-Fermi liquid and heavy fermion behavior in CexLa1-xB6CexLa1-xB6 with quadrupolar moments

The electrical resistivity of the cubic Kondo system CexLa1-xB6CexLa1-xB6 (x=0.1x=0.1–0.65) has been measured. Non-Fermi liquid behavior is found in paramagnetic phase I over the wide Ce concentration range. Heavy fermion behavior is found in ordered phases of Ce0.65La0.35B6Ce0.65La0.35B6. The mass enhancement of quasiparticles in this compound is strongly dependent of the magnetic field.

Non-Fermi liquid and heavy fermion behavior in CexLa1-xB6 with quadrupolar moments

The electrical resistivity of the cubic Kondo system CexLa1-xB6CexLa1-xB6 (x=0.1x=0.1–0.65) has been measured. Non-Fermi liquid behavior is found in paramagnetic phase I over the wide Ce concentration range. Heavy fermion behavior is found in ordered phases of Ce0.65La0.35B6Ce0.65La0.35B6. The mass enhancement of quasiparticles in this compound is strongly dependent of the magnetic field.