Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 21

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Quasi-one-dimensional magnetic interactions and conduction electrons in EuCu$$_5$$ and EuAu$$_5$$ with the characteristic hexagonal structure

Matsuda, Shinya*; Ota, Joji*; Nakaima, Kenri*; Iha, Wataru*; Gochi, Jun*; Uwatoko, Yoshiya*; Nakashima, Miho*; Amako, Yasushi*; Honda, Fuminori*; Aoki, Dai*; et al.

Philosophical Magazine, 100(10), p.1244 - 1257, 2020/04

 Times Cited Count:2 Percentile:45.37(Materials Science, Multidisciplinary)

Journal Articles

Spin glass behavior in EuCu$$_2$$Si$$_2$$ single crystal grown by the flux method

Takeuchi, Tetsuya*; Haga, Yoshinori; Taniguchi, Toshifumi*; Iha, Wataru*; Ashitomi, Yosuke*; Yara, Tomoyuki*; Kida, Takanori*; Tahara, Taimu*; Hagiwara, Masayuki*; Nakashima, Miho*; et al.

Journal of the Physical Society of Japan, 89(3), p.034705_1 - 034705_15, 2020/03

 Times Cited Count:0 Percentile:0(Physics, Multidisciplinary)

Journal Articles

Single crystal growth and unique electronic states of cubic chiral EuPtSi and related compounds

Onuki, Yoshichika*; Kakihana, Masashi*; Iha, Wataru*; Nakaima, Kenri*; Aoki, Dai*; Nakamura, Ai*; Honda, Fuminori*; Nakashima, Miho*; Amako, Yasushi*; Gochi, Jun*; et al.

JPS Conference Proceedings (Internet), 29, p.012001_1 - 012001_9, 2020/02

Journal Articles

Anomalous ferromagnetic ordering in EuCuP

Iha, Wataru*; Kakihana, Masashi*; Matsuda, Shinya*; Honda, Fuminori*; Haga, Yoshinori; Takeuchi, Tetsuya*; Nakashima, Miho*; Amako, Yasushi*; Gochi, Jun*; Uwatoko, Yoshiya*; et al.

Journal of Alloys and Compounds, 788, p.361 - 366, 2019/06

 Times Cited Count:2 Percentile:25.87(Chemistry, Physical)

Journal Articles

Effects of magnetic field and pressure on the valence-fluctuating antiferromagnetic compound EuPt$$_2$$Si$$_2$$

Takeuchi, Tetsuya*; Yara, Tomoyuki*; Ashitomi, Yosuke*; Iha, Wataru*; Kakihana, Masashi*; Nakashima, Miho*; Amako, Yasushi*; Honda, Fuminori*; Homma, Yoshiya*; Aoki, Dai*; et al.

Journal of the Physical Society of Japan, 87(7), p.074709_1 - 074709_14, 2018/07

 Times Cited Count:7 Percentile:63.33(Physics, Multidisciplinary)

Journal Articles

High pressure study on uranium heavy fermion compounds with antiferromagnetic ground state

Tateiwa, Naoyuki; Ikeda, Shugo*; Haga, Yoshinori; Matsuda, Tatsuma; Nakashima, Miho*; Aoki, Dai*; Settai, Rikio*; Onuki, Yoshichika

Journal of Physics; Conference Series, 150, p.042206_1 - 042206_4, 2009/03

 Times Cited Count:4 Percentile:88.15

We have studied the high pressure effect on the antiferromagnetic ground states of uranium heavy fermion compounds. In this paper we show our high pressure studies on U$$_2$$Zn$$_{17}$$ by the electrical resistivity measurements. In U$$_2$$Zn$$_{17}$$, the N$'e$el temperature $$T_{rm N}$$ in U$$_2$$Zn$$_{17}$$ decreases slightly from 9.66 K at 1 bar to 9.33 K at 2.5 GPa, becomes almost pressure-independent up to 4.7 GPa, and starts to increase at the higher pressure region. We discuss the pressure dependences of the coefficient of $$T^2$$ term in the electrical resistivity $$A$$, an antiferromagnetic gap $$Delta$$ and a characteristic temperature $$T_{{rho}{rm max}}$$. It is found that the effect of pressure on the electronic states in U$$_2$$Zn$$_{17}$$ is weak compared with the other heavy fermion compounds.

Journal Articles

Pressure effect of electrical resistivity and AC specific heat in CePtAl

Nakashima, Miho*; Ueda, Taiki*; Shimizu, Katsuya*; Nakashima, Hiroshi*; Thamizhavel, A.*; Tateiwa, Naoyuki; Haga, Yoshinori; Hedo, Masato*; Uwatoko, Yoshiya*; Settai, Rikio*; et al.

Journal of Magnetism and Magnetic Materials, 310(2, Part1), p.e9 - e11, 2007/03

We measured the electrical resistivity and AC-specific heat for a canted ferromagnet CePtAl under pressures using a diamond-anvilpressure cell. With increasing pressure, the magnetic ordering temperature $$T_{rm C1}$$ increases monotonously, becomes constant above 8 GPa and then starts to decrease steeply in a narrow pressure region from 10.3 to 10.9 GPa, indicating the first-order like phase transition. The similar pressure dependence of $$T_{rm C1}$$ was obtained in the AC-specific heat measurement.

Journal Articles

Magnetic and electrical properties in CePtSi$$_{3}$$ without inversion symmetry in the crystal structure

Kawai, Tomoya*; Okuda, Yusuke*; Shishido, Hiroaki*; Thamizhavel, A.*; Matsuda, Tatsuma; Haga, Yoshinori; Nakashima, Miho*; Takeuchi, Tetsuya*; Hedo, Masato*; Uwatoko, Yoshiya*; et al.

Journal of the Physical Society of Japan, 76(1), p.014710_1 - 014710_6, 2007/01

 Times Cited Count:18 Percentile:67.52(Physics, Multidisciplinary)

We succeeded in growing a single crystal of CePtSi$$_{3}$$ by the Sn-flux method. CePtSi$$_{3}$$ is found to be an antiferromagnet with two transitions at 4.8 and 2.4 K. Magnetic easy direction was [100] direction with an ordered moment of 1.15 $$mu_{rm B}$$/Ce. The anisotropy is similar to that of CeIrSi$$_{3}$$ in which the pressure-induced superconductivity was observed.

Journal Articles

Effect of pressure on the electronic state in antiferromagnets UPt$$_2$$Si$$_2$$ and UIr$$_2$$Si$$_2$$

Ikeda, Shugo; Nakashima, Miho*; Matsuda, Tatsuma; Tateiwa, Naoyuki; Yamamoto, Etsuji; Nakamura, Akio; Haga, Yoshinori; Hedo, Masato*; Uwatoko, Yoshiya*; Onuki, Yoshichika*

Journal of the Physical Society of Japan, 75(12), p.125003_1 - 125003_2, 2006/12

 Times Cited Count:1 Percentile:11.54(Physics, Multidisciplinary)

We measured the electrical resistivity under pressures up to 8 GPa in antiferromagnets UPt$$_2$$Si$$_2$$ ($$T_{rm N}$$ = 34 K) and UIr$$_2$$Si$$_2$$ ($$T_{rm N}$$ = 6.3 K). The N$$acute{rm e}$$el temperature is found to decrease slowly as a function of pressure in UPt$$_2$$Si$$_2$$. The critical pressure $$P_{rm c}$$ ($$T_{rm N}rightarrow$$ 0) is roughly estimated as $$P_{rm c}$$ $$simeq$$ 10 GPa. On the other hand, the N$$acute{rm e}$$el temperature is unchanged in UIr$$_2$$Si$$_2$$.

Journal Articles

Thermodynamics Investigation on pressure-induced superconductor CeNiGe$$_3$$ by ac calorimetry

Tateiwa, Naoyuki; Haga, Yoshinori; Matsuda, Tatsuma; Ikeda, Shugo; Nakashima, Miho*; Thamizhavel, A.*; Settai, Rikio*; Onuki, Yoshichika

Journal of the Physical Society of Japan, 75(Suppl.), p.174 - 176, 2006/08

We have investigated the physical properties of Heavy Fermion superconductors by the ac calorimetry under high pressure using a thermocouple. The method is powerful tool since the high sensitive measurement of the heat capacity is possible and the precise pressure dependence of transition temperatures such as the superconducting transition can be determined. In this conference, I would like to report our investigations on the heavy fermion superconductors CePt$$_3$$Si, CeNiGe$$_3$$ and UIr. We have made pressure phase diagram of these compounds and discuss the relation between the magnetism and superconductivity.

Journal Articles

The dHvA experiment under pressure in UIr

Shishido, Hiroaki*; Yamamoto, Etsuji; Haga, Yoshinori; Ikeda, Shugo; Nakashima, Miho*; Settai, Rikio*; Onuki, Yoshichika

Journal of the Physical Society of Japan, 75(Suppl.), p.119 - 120, 2006/08

 Times Cited Count:18 Percentile:68.78(Physics, Multidisciplinary)

no abstracts in English

Journal Articles

Anisotropic magnetic properties of Ce$$_2$$Ni$$_3$$Ge$$_5$$ single crystal

Thamizhavel, A.*; Sugitani, Ichiro*; Obiraki, Yoshiko*; Nakashima, Miho*; Okuda, Yusuke*; Matsuda, Tatsuma; Haga, Yoshinori; Takeuchi, Tetsuya*; Sugiyama, Kiyohiro*; Settai, Rikio*; et al.

Physica B; Condensed Matter, 378-380, p.841 - 842, 2006/05

 Times Cited Count:0 Percentile:0(Physics, Condensed Matter)

We have succeeded in growing single crystals of Ce$$_2$$Ni$$_3$$Ge$$_5$$, which crystallizes in the orthorhombic crystal structure, by the flux method and studied the anisotropic physical properties by measuring the electrical resistivity, magnetic susceptibility and specific heat. The results of these measurements indicate that Ce$$_2$$Ni$$_3$$Ge$$_5$$ undergoes two antiferromagnetic transitions at $$T_{N1}$$=4.9 K and $$T_{N2}$$=4.3 K. The electrical resistivity and susceptibility measurements reveal strong anisotropic magnetic properties. From the specific heat measurement the electronic specific heat coefficient was found to be 90mJ/K$$^2$$mol.

Journal Articles

Pressure-induced superconductivity of Ce$$_2$$Ni$$_3$$Ge$$_5$$

Nakashima, Miho*; Kohara, Hisanori*; Thamizhavel, A.*; Matsuda, Tatsuma; Haga, Yoshinori; Hedo, Masato*; Uwatoko, Yoshiya*; Settai, Rikio*; Onuki, Yoshichika

Physica B; Condensed Matter, 378-380, p.402 - 403, 2006/05

 Times Cited Count:7 Percentile:36.62(Physics, Condensed Matter)

The N$'e$el temperature of Ce$$_2$$Ni$$_3$$Ge$$_5$$ decreases with increasing pressure $$P$$ and becomes zero at a critical pressure $$Pc sim$$ 4 Gpa. The heavy fermion state was found to be formed around $$Pc$$, in which pressure region superconductivity was found below 0.26 K.

Journal Articles

Effect of pressure on electronic states in canted ferromagnet CePtAl

Ueda, Taiki*; Nakashima, Miho*; Hedo, Masato*; Uwatoko, Yoshiya*; Nakashima, Hiroshi*; Thamizhavel, A.*; Matsuda, Tatsuma; Haga, Yoshinori; Settai, Rikio*; Onuki, Yoshichika

Journal of the Physical Society of Japan, 74(12), p.3393 - 3394, 2005/12

 Times Cited Count:6 Percentile:42.78(Physics, Multidisciplinary)

no abstracts in English

Journal Articles

Anisotropic magnetic properties of a pressure-induced superconductor Ce$$_2$$Ni$$_3$$Ge$$_5$$

Thamizhavel, A.*; Nakashima, Hiroshi*; Obiraki, Yoshiko*; Nakashima, Miho*; Matsuda, Tatsuma; Haga, Yoshinori; Sugiyama, Kiyohiro*; Takeuchi, Tetsuya*; Settai, Rikio*; Hagiwara, Masayuki*; et al.

Journal of the Physical Society of Japan, 74(10), p.2843 - 2848, 2005/10

 Times Cited Count:12 Percentile:58.86(Physics, Multidisciplinary)

Single crystals of a pressure-induced superconductor Ce$$_2$$Ni$$_3$$Ge$$_5$$ have been successfully grown by the flux method. The anisotropic magnetic properties due to the orthorhombic crystal structure have been studied precisely by the electrical resistivity, specific heat, magnetic susceptibility, and high-field magnetization measurements. The results of these measurements confirmed two antiferromagnetic transitions at T$$_{N1}$$=5.0 K and T$$_{N2}$$=4.3 K. The electronic specific heat coefficient obtained from the low-temperature specific heat data amounts to 90 mJ/K$$^2$$mol Ce. The high-field magnetization for H //[100] shows four magnetic transitions at 11.8, 12.9, 17.5 and 23.9 T with a saturation moment of 0.73 $$mu_B$$/Ce at 1.3 K. We have also performed the crystalline electric field (CEF) analysis on the magnetic susceptibility and magnetization to understand the magnetocrystalline anisotropy, where the splitting energies of two excited doublets in the CEF scheme are estimated to be 140 and 576 K, respectively.

Journal Articles

Single crystal growth and fermi surface properties of an antiferromagnet UPdGa$$_5$$

Ikeda, Shugo; Matsuda, Tatsuma; Haga, Yoshinori; Yamamoto, Etsuji; Nakashima, Miho*; Kirita, Shingo*; Kobayashi, Tatsuo*; Hedo, Masato*; Uwatoko, Yoshiya*; Yamagami, Hiroshi*; et al.

Journal of the Physical Society of Japan, 74(8), p.2277 - 2281, 2005/08

 Times Cited Count:10 Percentile:54.78(Physics, Multidisciplinary)

We have succeeded in growing a high-quality single crystal of an antiferromagnet UPdGa$$_5$$ by the Ga-flux method with the off-stoichiometric composition of U : Pd : Ga = 1 : 2 : 7.3. The electronic state has been investigated by the de Haas-van Alphen experiment, indicating the similar cylindrical Fermi surfaces as in an antiferromagnet UPtGa$$_5$$. We have also studied the pressure effect by measuring the electrical resistivity. The N$$acute{rm e}$$el temperature decreases with increasing pressure and becomes zero at 3.1 GPa. The antiferromagnetic state is changed into the paramagnetic state above 3.1 GPa.

Journal Articles

Pressure effect on antiferromagnetic ordering in UPb$$_3$$

Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika; Nakashima, Miho*; Aoki, Dai*; Onuki, Yoshichika*; Hedo, Masato*; Uwatoko, Yoshiya*

Acta Physica Polonica B, 34(2), p.1239 - 1242, 2003/02

Uranium intermetallic compounds UX$$_3$$ (X = Si, Ge, Sn, Pb) form a ariety of magnetic properties including Pauli paramagnetism in USi$$_3$$ and UGe$$_3$$, spin fluctuations in USn$$_3$$ and antiferromagnetism in UPb$$_3$$. Among them, UPb$$_3$$ is an antiferromagnet below the N$'e$el temperature 32 K with a large electronic specific heat $$gamma$$ = 110 mJ/K$$^2$$mol. In this study we present the electrical resistivity measurement under high pressure up to 8 GPa. We found that at low pressure $$T_{rm N}$$ increases with increasing pressure. It has a maximum value 36 K at 3 GPa, then decreases with increasing pressure.In addition we observed an additional resistive anomaly followed by a steep decrease in resistivity below $$T_{rm N}$$ under pressure.The maximum pressure 8 GPa in the present study was not enough to suppress the antiferromagnetic transition.The critical pressure is estimated to be around 12 GPa.

Journal Articles

Superconductivity in CeRh$$_{2}$$Si$$_{2}$$ under pressure

Araki, Shingo; Nakashima, Miho*; Settai, Rikio*; Kobayashi, Tatsuo*; Onuki, Yoshichika

Acta Physica Polonica B, 34(2, Part1), p.439 - 442, 2003/02

no abstracts in English

Oral presentation

Investigation on the heavy fermion superconductors by the ac heat capacity measurement

Tateiwa, Naoyuki; Haga, Yoshinori; Matsuda, Tatsuma; Ueda, Taiki*; Thamizhavel, A.*; Nakashima, Miho*; Takeuchi, Tetsuya*; Settai, Rikio*; Onuki, Yoshichika; Knebel, G.*; et al.

no journal, , 

We have developed the system for the heat capacity measurement by the thermocouple in order to study the high pressure physical properties of the rare earth and actinide compounds. In this talk, we would like to show our system and discuss our recent results on the heavy fermion superconductors CePt$$_3$$Si and UIr. It is noted that the superconductivity of UIr was found by our group. There is no inversion center in crystal structures of both compounds. The superconductivity of both compounds might be the novel type. In the case of CePt$$_3$$Si, the antiferromagnetic phase is strongly suppressed by the applied pressure and disappears above 0.6 GPa, while the superconducting phase exists in the wide pressure region up to 1.5 GPa. It is found that the overall feature of the pressure phase diagram is different from those of other heavy fermion superconductors. In the case of UIr, it is suggested by the resistivity measurement under pressures that there exists multiple ferromagnetic phases in the high pressure region. We investigated the pressure phase diagram of UIr from the thermodynamic point of view. We discuss the relation between the superconductivity and magnetism in UIr.

Oral presentation

Thermodynamics study on the heavy fermion superconductor under high pressure

Tateiwa, Naoyuki; Haga, Yoshinori; Matsuda, Tatsuma; Ikeda, Shugo; Nakashima, Miho*; Thamizhavel, A.*; Takeuchi, Tetsuya*; Settai, Rikio*; Onuki, Yoshichika

no journal, , 

I will show our recent investigations on the heavy femion superconductors by the ac calorimetry method under pressure. The method is powerful tool since the high sensitive measurement of the heat capacity is possible. I will present our study on superconductivity in CePt$$_3$$Si with the non-centrosymmetric tetragonal structure. Superconductivity with the transition temperature $$T_{rm sc}$$=0.75K is realized in the long-range antiferromagnetic ordered state with the N$'e$el temperature $$T_{rm N}$$=2.2K. We determine the pressure phase diagram of CePt$$_3$$Si. The N$'e$el temperature decreases with increasing pressure and becomes zero at the critical pressure $$P_{rm AF}$$$$simeq$$0.6GPa. On the other hand, the superconducting phase exists in a wider pressure region from ambient pressure to about 1.5 GPa. There is no anomalous singular behavior in the pressure dependences of the electronic specific heat coefficient $$gamma$$ around $$P_{rm AF}$$. This suggests that the superconductivity in CePt$$_3$$Si differs from those observed around the quantum critical point such as in CeIn$$_3$$.

Oral presentation

Heat capacity measurement on the pressure induced Ce superconductors

Tateiwa, Naoyuki; Haga, Yoshinori; Matsuda, Tatsuma; Shishido, Hiroaki*; Nakashima, Miho*; Takeuchi, Tetsuya*; Settai, Rikio*; Onuki, Yoshichika*

no journal, , 

We have perfomed the ac heat capacity measurement on the Ce-based pressure induced superconductor. In this meeting, We will show our experimental results as well as the experimental apparatuses for the measuremnt. Especially, we will focus on the pressure induced superconductor CeNiGe$$_3$$ that orders antiferromagnetically at 5.5K at ambient pressure. The transition temperature increases with increasing pressure, becomes maximum around 3GPa, and then decreases with the higher pressure region. The antiferromagnetic critical pressure is around 7GPa. We performed the ac heat capacity measurement under high pressure. The superconducting anomaly due to the superconducting transition was observed around 0.3K. From this observation, we concluded the bulk nature of the superconductivity.

21 (Records 1-20 displayed on this page)