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Abstract: We have carried out the de Haas–van Alphen (dHvA) experiment of an antiferromagnet under pressure. The detected dHvA branches and at ambient pressure are well explained by the corresponding dHvA branches in , indicating that the f electron is localized at ambient pressure. At 2.9GPa, where the antiferromagnetic ordering disappears completely, a new branch appears. This is approximately the same as that of 4f-itinerant Fermi surface in , suggesting that the 4f electronic state is changed into an itinerant one. [Copyright &y& Elsevier]

Abstract: We measured the heat capacity of CeIrSi3 (100mK

Abstract: We grew high-quality single crystals of and succeeded in observing the de Haas–van Alphen effect. The metamagnetic transition, where the antiferromagnetic state changes into the paramagnetic (field-induced ferromagnetic) state, was observed at for . On increasing the field angle , follows the dependence, indicating an Ising-type antiferromagnet. The main Fermi surface in consists of two kinds of cylindrical ones. The detected cyclotron effective mass is considerably large, ranging from to in the paramagnetic state. is a heavy-fermion compound and the 5f electrons significantly contribute to the conduction bands. [Copyright &y& Elsevier]

Abstract: CePt3Si shows an antiferromagnetic order at and enters into a heavy fermion superconducting state at . We observed the appearance of clear antiferromagnetic reflections with below . The observed antiferromagnetic peak exists even below , namely, the superconductivity coexists with antiferromagnetic order in CePt3Si. The magnetic moments of lying in the basal plane order ferromagnetically in the c-plane with inversion center, and are stacked antiferromagnetically along the c-axis with lack of inversion symmetry. Clear crystal field excitations were observed at 1 and 24meV. The magnetic susceptibility was consistent with the level scheme assuming the . [Copyright &y& Elsevier]

Abstract: We measured the magnetic susceptibility and magnetization of an antiferromagnet Ce3Sn7 with the orthorhombic crystal structure. The experimental data are found to be well explained on the basis of the crystalline electric field (CEF) 4f-scheme under the assumption that two Ce atoms in the 2(a) site possess a magnetic moment of and one Ce atom in the 4(i) site possesses no magnetic moment as in a valence fluctuating compound CeSn3, which was previously proposed by Bonnet et al. Furthermore, we carried out the de Haas–van Alphen experiment. The detected Fermi surfaces are many in number but are extremely small in volume, indicating that Ce3Sn7 is a semimetal. [Copyright &y& Elsevier]

Abstract: We have measured the electrical resistivity of antiferromagnetic Kondo compounds and under pressure. In , Néel temperature initially increases with increasing pressure up to 3GPa, then decreases rather steeply with further increasing pressure, and becomes zero at a critical pressure . The and values of the resistivity in the Fermi liquid relation become maximum around . Superconductivity is found below 0.48K in a wide pressure region from 4 to 10GPa. In , the similar pressure dependence of is found, has a maximum at 3.9GPa, and becomes zero around 6GPa. [Copyright &y& Elsevier]

Abstract: We grew a single crystal of an antiferromagnetic CeRhGe and studied the electronic state by measuring the electrical resistivity, magnetic susceptibility, magnetization and neutron scattering. The magnetic susceptibility is found to be highly anisotropic, reflecting the orthorhombic crystal structure. The antiferromagnetic structure is, however, not simple, as expected from the results of the susceptibility. The resistivity peaks at the Néel temperature, which was observed under pressure, is pronounced with increasing pressure up to 1.3–1.5GPa. [Copyright &y& Elsevier]