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Papers by Takanori Tsutaoka

Journal of Magnetism and Magnetic Materials, 2007

Electrical resistivity r has been measured for the rare earth intermetallic compounds R 7 Rh 3 (R... more Electrical resistivity r has been measured for the rare earth intermetallic compounds R 7 Rh 3 (R ¼ Dy and Y) under high pressure up to 3.0 GPa in the temperature range from 2 to 300 K. Y 7 Rh 3 and Dy 7 Rh 3 show semiconductive behavior at high temperatures under ambient pressure. The semicouductive character is slightly suppressed in Y 7 Rh 3 but is slightly enhanced in Dy 7 Rh 3 under pressure. Neel temperature of Dy 7 Rh 3 does not change up to 3.0 GPa, indicating the antiferromagnetic structure is stable under compression. r

The Annals of Educational Research, Mar 24, 2011

Acta Phys Pol B, 2003

Magnetic and transport properties of (YxCe1-x)7Rh3 have been studied by measuring magnetization, ... more Magnetic and transport properties of (YxCe1-x)7Rh3 have been studied by measuring magnetization, magnetic susceptibility and electrical resistivity. Ce7Rh3 is a metal ferromagnet and Y7Rh3 is a semimetallic Pauli paramagnet. In (YxCe1-x)7Rh3, ferromagnetic phase disappears at about x = 0.4. Intermediate valence state can exist in high Y concentration range above x = 0.5. In this range, electrical properties can be realized by the Kondo scattering in semimetallic band structure.

The Annals of Educational Research, Mar 26, 2012

Journal of Magnetism and Magnetic Materials, May 1, 2004

Single crystals of Gd5Ge3 and Tb5Ge3 have been successfully grown by the Czochralski method. Gd5G... more Single crystals of Gd5Ge3 and Tb5Ge3 have been successfully grown by the Czochralski method. Gd5Ge3 shows antiferromagnetic below TN=76K and has no magnetic anisotropy in the paramagnetic susceptibility; another antiferromagnetic phase transition has been found at Tt=52K. In contrast, Tb5Ge3 shows a large magnetic anisotropy and antiferromagnetic below TN=79K. In antiferromagnetic phase, magnetic moments tend to be aligned in the c-plane for both Gd5Ge3 and Tb5Ge3.

The Annals of Educational Research, Mar 31, 2010

The Annals of Educational Research, Mar 31, 2010

The Annals of Educational Research, Mar 20, 2007

J Alloys Compounds, 2007

Intermetallic compounds Tb7Rh3 and Dy7Rh3, which crystallize in Th7Fe3 type hexagonal structure w... more Intermetallic compounds Tb7Rh3 and Dy7Rh3, which crystallize in Th7Fe3 type hexagonal structure with the space group P63mc were hydrogenated under high hydrogen pressure in order to study influence of hydrogen on their structural and magnetic properties.Hydrogen treatment of Tb7Rh3 and Dy7Rh3 even at moderate pressures resulted in formation of hydrides with H/M > 2. The hydrides retained symmetry of parent materials but large lattice expansion has been observed. After release of hydrogen pressure the hydrides were stable and could be kept for long time at normal conditions. Hydrogenation affects strongly magnetic properties of both Tb7Rh3 and Dy7Rh3. Treatment at 100 °C up to 10 kbar (H2) did not cause their amorphisation or decomposition.

Bulletin of the Graduate School of Education Hiroshima University Part Ii Arts and Science Education, Mar 28, 2005

Journal of Vacuum Science Technology B Microelectronics and Nanometer Structures, Nov 1, 1990

J Magn Magn Mater, 1998

Electrical resistivity of Nd7Ni3 shows anomalies at the Néel temperature TN = 29 K and the Curie ... more Electrical resistivity of Nd7Ni3 shows anomalies at the Néel temperature TN = 29 K and the Curie temperature Tc = 14 K but does not show any change at the spin reorientation temperature TR = 8.7 K. The thermoelectric power has also broad humps around 250 and 50 K as well as a sharp break at TN and a minimum at 10 K. The corresponding Hall coefficient shows anomalies at TN, Tc and TR, following the Curie—Weiss-law-like behavior above TN.

Physical Review B, Nov 1, 1985

Measurements of the ac magnetic susceptibility, magnetization, and electrical resistivity at hydr... more Measurements of the ac magnetic susceptibility, magnetization, and electrical resistivity at hydrostatic pressures up to 15 kbar and of the thermal expansion were made for the EuxYb1-x alloy system (x<=0.4) in temperatures from 1.6 to 400 K. The paramagnetic-ferromagnetic transition temperature Tc versus pressure p curve for x=0.025 has a maximum near p=1 kbar. For x=0.25, Tc decreases and the ferromagnetic-spin-glass-like transition temperature Tt increases at rates of ΔTc/Δp=-9.5 K/kbar and ΔTt/Δp=+1.7 K/kbar, respectively. The ferromagnetic region disappears near p=2.5 kbar, and above it the paramagnetic-spin-glass-like transition temperature Tg, which is pressure insensitive, appears. The Tg value for x=0.35 decreases initially and increases slowly with increasing p above p=2 kbar at a rate of ΔTg/Δp=+0.15 K/kbar. Both the magnetization in the ferromagnetic concentration range and the value of the ac magnetic susceptibility near Tg in the spin-glass-like state decrease with increasing p. From electrical-resistivity measurements under various pressures, semiconducting character was observed at the ambient pressure for x=0.35 and the transition from semimetallic to semiconducting states appears with increasing p for x=0.025. Thermal expansion shows the large positive volume magnetostriction. These results of the measurements under pressure are discussed on the basis of the Ruderman-Kittel-Kasuya-Yosida interaction by considering that the dominant variable is the number of carriers (electrons or holes) which is strongly controlled by the pressure.

Bulletin of the Graduate School of Education Hiroshima University Part Ii Arts and Science Education, Mar 28, 2005

Physica B, 2001

The high-field magnetization has been studied for the intermetallic compounds R7Rh3 (R=Tb, Dy and... more The high-field magnetization has been studied for the intermetallic compounds R7Rh3 (R=Tb, Dy and Ho) in magnetic fields up to 280 kOe at 1.5 K. In Tb7Rh3, three successive metamagnetic transitions accompanied by a large hysteresis were found. On the other hand, metamagnetic transitions in Ho7Rh3 were identified by small anomalies in the M–H curves. Dy7Rh3 has large magnetic anisotropy and has four metamagnetic transitions with hysteresis. In all these compounds, the magnetization is not saturated even at 280 kOe. The metamagnetic transitions indicate the occurrence of complex magnetic structures in these compounds.

2015 7th Asia-Pacific Conference on Environmental Electromagnetics (CEEM), 2015

Journal of the Physical Society of Japan, 2001

Journal of the Physical Society of Japan, 2001

Physica B Condensed Matter, 2006

Magnetic and neutron diffraction studies have been performed on an Er 7 Rh 3 single crystal. The ... more Magnetic and neutron diffraction studies have been performed on an Er 7 Rh 3 single crystal. The magnetic measurements show that there are two successive antiferromagnetic transitions at T N ¼ 13.0 K and T t1 ¼ 6.2 K. A small magnetic anisotropy is observed in the paramagnetic susceptibility. Neutron diffraction also shows evidence of a commensurate to incommensurate magnetic transition at T t2 ¼ 4.5 K. The magnetic structure in the low temperature antiferromagnetic phase below T t2 is characterized by the two magnetic propagation vectors k 1 ¼ (0 0 1/2) and k 2 ¼ (0 0 1). With increasing temperature, the magnetic modulation characterized by k 2 disappears at T t1 but the z-component is temperature independent. On the other hand, the magnetic modulation characterized by k 1 becomes incommensurate at T t2 where k 1 ¼ (0 0 0.42) and persists in the high temperature phase between T t1 and T N . Fig. 3. Peak intensity of the magnetic reflections of (2 0 0) + and (2 0 0) m and k 1z as a function of temperature. Solid lines are guide for the eyes.

Journal of Magnetism and Magnetic Materials, 2007

Electrical resistivity r has been measured for the rare earth intermetallic compounds R 7 Rh 3 (R... more Electrical resistivity r has been measured for the rare earth intermetallic compounds R 7 Rh 3 (R ¼ Dy and Y) under high pressure up to 3.0 GPa in the temperature range from 2 to 300 K. Y 7 Rh 3 and Dy 7 Rh 3 show semiconductive behavior at high temperatures under ambient pressure. The semicouductive character is slightly suppressed in Y 7 Rh 3 but is slightly enhanced in Dy 7 Rh 3 under pressure. Neel temperature of Dy 7 Rh 3 does not change up to 3.0 GPa, indicating the antiferromagnetic structure is stable under compression. r

The Annals of Educational Research, Mar 24, 2011

Acta Phys Pol B, 2003

Magnetic and transport properties of (YxCe1-x)7Rh3 have been studied by measuring magnetization, ... more Magnetic and transport properties of (YxCe1-x)7Rh3 have been studied by measuring magnetization, magnetic susceptibility and electrical resistivity. Ce7Rh3 is a metal ferromagnet and Y7Rh3 is a semimetallic Pauli paramagnet. In (YxCe1-x)7Rh3, ferromagnetic phase disappears at about x = 0.4. Intermediate valence state can exist in high Y concentration range above x = 0.5. In this range, electrical properties can be realized by the Kondo scattering in semimetallic band structure.

The Annals of Educational Research, Mar 26, 2012

Journal of Magnetism and Magnetic Materials, May 1, 2004

Single crystals of Gd5Ge3 and Tb5Ge3 have been successfully grown by the Czochralski method. Gd5G... more Single crystals of Gd5Ge3 and Tb5Ge3 have been successfully grown by the Czochralski method. Gd5Ge3 shows antiferromagnetic below TN=76K and has no magnetic anisotropy in the paramagnetic susceptibility; another antiferromagnetic phase transition has been found at Tt=52K. In contrast, Tb5Ge3 shows a large magnetic anisotropy and antiferromagnetic below TN=79K. In antiferromagnetic phase, magnetic moments tend to be aligned in the c-plane for both Gd5Ge3 and Tb5Ge3.

The Annals of Educational Research, Mar 31, 2010

The Annals of Educational Research, Mar 31, 2010

The Annals of Educational Research, Mar 20, 2007

J Alloys Compounds, 2007

Intermetallic compounds Tb7Rh3 and Dy7Rh3, which crystallize in Th7Fe3 type hexagonal structure w... more Intermetallic compounds Tb7Rh3 and Dy7Rh3, which crystallize in Th7Fe3 type hexagonal structure with the space group P63mc were hydrogenated under high hydrogen pressure in order to study influence of hydrogen on their structural and magnetic properties.Hydrogen treatment of Tb7Rh3 and Dy7Rh3 even at moderate pressures resulted in formation of hydrides with H/M > 2. The hydrides retained symmetry of parent materials but large lattice expansion has been observed. After release of hydrogen pressure the hydrides were stable and could be kept for long time at normal conditions. Hydrogenation affects strongly magnetic properties of both Tb7Rh3 and Dy7Rh3. Treatment at 100 °C up to 10 kbar (H2) did not cause their amorphisation or decomposition.

Bulletin of the Graduate School of Education Hiroshima University Part Ii Arts and Science Education, Mar 28, 2005

Journal of Vacuum Science Technology B Microelectronics and Nanometer Structures, Nov 1, 1990

J Magn Magn Mater, 1998

Electrical resistivity of Nd7Ni3 shows anomalies at the Néel temperature TN = 29 K and the Curie ... more Electrical resistivity of Nd7Ni3 shows anomalies at the Néel temperature TN = 29 K and the Curie temperature Tc = 14 K but does not show any change at the spin reorientation temperature TR = 8.7 K. The thermoelectric power has also broad humps around 250 and 50 K as well as a sharp break at TN and a minimum at 10 K. The corresponding Hall coefficient shows anomalies at TN, Tc and TR, following the Curie—Weiss-law-like behavior above TN.

Physical Review B, Nov 1, 1985

Measurements of the ac magnetic susceptibility, magnetization, and electrical resistivity at hydr... more Measurements of the ac magnetic susceptibility, magnetization, and electrical resistivity at hydrostatic pressures up to 15 kbar and of the thermal expansion were made for the EuxYb1-x alloy system (x<=0.4) in temperatures from 1.6 to 400 K. The paramagnetic-ferromagnetic transition temperature Tc versus pressure p curve for x=0.025 has a maximum near p=1 kbar. For x=0.25, Tc decreases and the ferromagnetic-spin-glass-like transition temperature Tt increases at rates of ΔTc/Δp=-9.5 K/kbar and ΔTt/Δp=+1.7 K/kbar, respectively. The ferromagnetic region disappears near p=2.5 kbar, and above it the paramagnetic-spin-glass-like transition temperature Tg, which is pressure insensitive, appears. The Tg value for x=0.35 decreases initially and increases slowly with increasing p above p=2 kbar at a rate of ΔTg/Δp=+0.15 K/kbar. Both the magnetization in the ferromagnetic concentration range and the value of the ac magnetic susceptibility near Tg in the spin-glass-like state decrease with increasing p. From electrical-resistivity measurements under various pressures, semiconducting character was observed at the ambient pressure for x=0.35 and the transition from semimetallic to semiconducting states appears with increasing p for x=0.025. Thermal expansion shows the large positive volume magnetostriction. These results of the measurements under pressure are discussed on the basis of the Ruderman-Kittel-Kasuya-Yosida interaction by considering that the dominant variable is the number of carriers (electrons or holes) which is strongly controlled by the pressure.

Bulletin of the Graduate School of Education Hiroshima University Part Ii Arts and Science Education, Mar 28, 2005

Physica B, 2001

The high-field magnetization has been studied for the intermetallic compounds R7Rh3 (R=Tb, Dy and... more The high-field magnetization has been studied for the intermetallic compounds R7Rh3 (R=Tb, Dy and Ho) in magnetic fields up to 280 kOe at 1.5 K. In Tb7Rh3, three successive metamagnetic transitions accompanied by a large hysteresis were found. On the other hand, metamagnetic transitions in Ho7Rh3 were identified by small anomalies in the M–H curves. Dy7Rh3 has large magnetic anisotropy and has four metamagnetic transitions with hysteresis. In all these compounds, the magnetization is not saturated even at 280 kOe. The metamagnetic transitions indicate the occurrence of complex magnetic structures in these compounds.

2015 7th Asia-Pacific Conference on Environmental Electromagnetics (CEEM), 2015

Journal of the Physical Society of Japan, 2001

Journal of the Physical Society of Japan, 2001

Physica B Condensed Matter, 2006

Magnetic and neutron diffraction studies have been performed on an Er 7 Rh 3 single crystal. The ... more Magnetic and neutron diffraction studies have been performed on an Er 7 Rh 3 single crystal. The magnetic measurements show that there are two successive antiferromagnetic transitions at T N ¼ 13.0 K and T t1 ¼ 6.2 K. A small magnetic anisotropy is observed in the paramagnetic susceptibility. Neutron diffraction also shows evidence of a commensurate to incommensurate magnetic transition at T t2 ¼ 4.5 K. The magnetic structure in the low temperature antiferromagnetic phase below T t2 is characterized by the two magnetic propagation vectors k 1 ¼ (0 0 1/2) and k 2 ¼ (0 0 1). With increasing temperature, the magnetic modulation characterized by k 2 disappears at T t1 but the z-component is temperature independent. On the other hand, the magnetic modulation characterized by k 1 becomes incommensurate at T t2 where k 1 ¼ (0 0 0.42) and persists in the high temperature phase between T t1 and T N . Fig. 3. Peak intensity of the magnetic reflections of (2 0 0) + and (2 0 0) m and k 1z as a function of temperature. Solid lines are guide for the eyes.