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The high pressure effect on resistance of the LB film of ditetradecyldimethylammonium-Au(dmit)2 [2C14N+Me2-Au(dmit)2] salt has been investigated; the measurements were performed down to 0.8 K and pressures up to 1.03 GPa using a clamptype pressure cell. The resistance gradually decreases with increasing pressure reaching a 57% smaller value at 1.03 GPa compared to the ambient one. The resistance increases with decreasing temperature for three different conditions of the measurement: at 0 GPa and under pressure (clamped at 0.80 GPa and 1.03 GPa) in the temperature range of 18−295 K. Over the whole temperature range, the higher the pressure is, the lower the sheet resistance is, indicating that the application of pressure is effective to reduce the sheet resistance. Although we have already reported the magnetic anomaly suggesting the Meissner state in the LB film below 3.9 K, no resistance drop is observed even if the resistance was measured down to 0.8 K.

Magnetic and specific heat measurements have been performed on a GdPd2Si2 single crystal compound having the tetragonal ThCr2Si2-type crystal structure. Specific heart shows two λ-type anomalies at TN=16.7 K, T1=12.3 K and a small hump with hysteresis at T2=6.8 K; there are three phases below TN. The magnetic entropy of Rln6 is released below TN. The temperature dependence of magnetic susceptibility shows a very peculiar behaviour. With decreasing temperature, the magnetic susceptibility along the [001] direction increases through a small kink at TN down to T1 where a clear cusp is seen, decreases rapidly below TN, then shows an upturn and a clear kink at T2 followed by a gradual increase. This behaviour examines at various magnetic field along [001] and [100]. The B001-T and B100-T magnetic phase diagrams have been constructed. The field-induced phase appears near by the 100] magnetic field, B100.

The B-T magnetic phase diagrams for TbCu2Si2 single crystal, having the tetragonal ThCr2Si2-type crystal structure, have been constructed from magnetic measurements. The compound orders antiferromagneticaly below TN=11.9 K and shows another magnetic transition at Tt=9.1 K. In the easy magnetization direction of [110], a six-step metamagnetic process appears at low temperatures. Above Tt, it becomes a two-step metamagnetic one. There are seven ordered magnetic phases below the paramagnetic region in the B110-T magnetic phase diagram. In the [100] magnetization process, three metamagnetic transitions appear at low temperatures. The magnetization process becomes a one-step one above Tt. The B100-T phase diagram, composed of four phases, is very peculiar; a quad-critical point may appear. The magnetic structure for each phase has been discussed.

We have measured the electrical resistivity of YbT2Zn20 (T = Ir, Rh) single crystals under pressure up to 2.4 GPa. We found that the resistivity of both compounds shows a pronounced maximum Tmax under pressure as seen in YbCo2Zn20 at ambient pressure. The temperature Tmax decreases with increasing pressure, reflecting the lowering of the Kondo temperature TK. Low temperature resistivity behaves as expected for a conventional Landau Fermi liquid ρ = ρ0 + AT2. The A coefficient is strongly enhanced upon applying pressure and can be related to the Tmax by A−1/2 Tmax. This relation holds for YbT2Zn20 (T = Ir, Rh and Co) compounds in the pressure range investigated here, suggesting the validity of the Fermi liquid description in this system.

57Fe nuclear resonant forward scattering experiment has been performed on a single crystalline Fe2P under multi-extreme conditions, which shows a pressure induced ferromagnteic-antiferromagetic transition and magnetic field induced metamagnetic transition. We present the clear experimental evidence that internal magnetic fields in two Fe sites at 3 K, 25 kOe and 2.5 GPa are comparable with those in a ferromagnetic state at ambient pressure. These internal magnetic fields, which are related to magnetic moments, are not aligned collinearly along the [001] axis by the external magnetic field.