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Neutron scattering experiments have been carried out that reveal the magnetic excitation in the ferromagnet CeAgSb2. Crystalline electric field excitations were observed at 5.2 and 12.5 meV in the paramagnetic state, indicative of the localized nature of the Ce 4f electron. Our analysis concluded that |Jz = ±1/2 is the ground state, while the first and second excited levels are mainly due to |±3/2 and |±5/2, respectively. The observed ferromagnetic moment is in good agreement with the ground-state saturation moment, gJμBJz ~ 0.43 μB. The spin wave dispersion is interpreted using the anisotropic Heisenberg model with ferromagnetic exchange interaction up to seventh-nearest neighbours. The spontaneous moment along the c-axis decreases with increasing field perpendicular to the c-axis, and disappears at the critical field Hc, which corresponds to the anomaly which appeared in the magnetization curve.

We have performed the de Haas-van Alphen (dHvA) and ac-susceptibility experiments on a ferromagnet UGe2 under pressure for the field along the easy a-axis. The p-H phase diagram was determined, indicating three kinds of phase: paramagnetic and weakly and strongly polarized phases. The detected dHvA frequencies as well as the cyclotron masses are found to be very different between the weakly and strongly polarized states. A change of the Fermi surface occurs when the weakly polarized phase is changed into the strongly polarized phase with increasing magnetic field.

We carried out the de Haas-van Alphen (dHvA) experiment under pressure for a ferromagnet UGe2. The dHvA frequency of a main dHvA branch named α, that corresponds to a majority up-spin band 40-hole Fermi surface, decreases monotonously with increasing pressure, but in the pressure range from pc* (1.2 GPa) to pc (1.5 GPa) the dHvA signal disappears completely, where pc and pc* correspond to critical pressures for a Curie temperature TC and the second phase transition temperature T* ( pc we observed new dHvA branches with large cyclotron masses of 19-64m0, which correspond to main Fermi surfaces in the paramagnetic state.

We examine magnetic ordering in CePd2P2 by neutron-scattering experiment and confirmed a ferromagnetic order at low temperatures. From the neutron-scattering data, the ordered moment is evaluated to be ~ 1.3(3) μB per Ce ion at 3 K and is considered to be parallel to the c-axis. In addition, no evidence of the change in the magnetic structure was observed below TC within the experimental accuracy. In DC magnetization measurement with an as-grown powder sample and a magnetically aligned sample, a clear magnetic anisotropy in CePd2P2 was observed in both ferromagnetic and paramagnetic phases. To obtain further insight to the large Curie temperature TC of CePd2P2, we have examined the magnetic properties of GdPd2P2 as a reference material. In DC magnetization measurement, successive magnetic transitions at TI = 10.6 K and TII = 7.4 K were observed in GdPd2P2. By comparing the transition temperatures of the Ce and Gd compounds, we argue the origin of the large Curie temperature of CePd2P2.

We have measured 63Cu-NQR spectral lines and nuclear spin-lattice relaxation time T1 under pressure up to 5.4 GPa. Daphne oil 7474 is used as the pressure-transmitting medium to obtain good hydrostaticity. NQR frequency 63νq above 4 GPa suddenly decreases from the linear pressure dependence in the low pressure range (P ≤ 3.5 GPa). The observed sudden downward deviation of 63νq is associated with an increase of Ce valence. Above 4.5 GPa, the linear pressure dependence of 63νq is observed again, most likely related to the sharp crossover to the high valence state.

Hall effect measurements were carried out under high pressures up to 4.9 GPa in a single crystal of CeCu2Si2. The temperature dependence of the Hall coefficient is interpreted to be composed of two peaks below room temperature. The high-temperature peak shows strong pressure dependence, where the peak shifts from 20 K at ambient pressure to 125 K at 4.9 GPa. This peak is a consequence of the anomalous Hall effect due to skew scattering. The low-temperature peak shifts from 5 K at ambient pressure to 15 K at 4.9 GPa and the magnitude of the peak shows the maximum around 4.1 GPa at which the superconducting transition temperature also reaches the maximum.

Low-silica X (LSX) zeolite has the FAU-type framework structure constructed of supercages and β-cages with effective inside diameters of 13 and 7 A, respectively. Respective cages are arrayed in a diamond structure. Na-K clusters are formed by the loading of guest potassium atoms nK into LSX, where the unloaded LSX has 4Na and 8K zeolite-cations per supercage (or β-cage) as given by Na4K8Al12Si12O48. N-type ferrimagnetism has been observed at ambient loading densities of K atoms, 6.5 < n < 8.5. Ferrimagnetism was not observed at the maximum loading density at ambient pressure, n ≈ 9. In the present study, we extended the loading density for 9 < n by the pressure-loading technique. Spontaneous magnetization is observed again below 10.5 and 9.1 K at the loading pressures ≈ 400 and ≈ 520 MPa, respectively. Respective Weiss temperatures are −23 and −32 K. These results indicate that the ferrimagnetism appears again at higher loading densities.