JAEA
  • help
  • PC | SP
  • JP | EN
          
検索対象：     
報告書番号：
※ 半角英数字
 年 ～ 
 年
全てクリア
検索結果：　157 件中 1件目～20件目を表示

発表形式

Initialising ...

選択項目を絞り込む

掲載資料名

Initialising ...

発表会議名

Initialising ...

筆頭著者名

Initialising ...

キーワード

Initialising ...

使用言語

Initialising ...

発行年

Initialising ...

開催年

Initialising ...

選択した検索結果をダウンロード

論文

Local atomic displacements and sign of the structural transformation in medium-entropy alloys observed in extended X-ray absorption fine structure spectra

池田 陽一*; 梅本 好日古*; 松村 大樹; 辻 卓也; 橋本 勇輝*; 北澤 崇文*; 藤田 全基*

Materials Transactions, 64(9), p.2254 - 2260, 2023/09

https://doi.org/10.2320/matertrans.MT-M2023043
 被引用回数：0

Extended X-ray absorption fine structure (EXAFS) and neutron diffraction experiments were carried out to clarify the typical features of the local structure of a family of medium-entropy alloys (CrCoNi, MnCoNi, and FeCoNi). A simple random cluster model was constructed for analyzing EXAFS spectra, and static and dynamic components of the mean-square relative displacement (MSRD) were separately extracted. In our analysis, the static MSRD of the MnCoNi sample was slightly larger than those of the CrCoNi and FeCoNi samples, whereas the dynamic MSRDs of these samples were almost identical. Based on the complementary neutron diffraction data, we argued that the origin of the large static displacement in the MnCoNi alloy can be associated with a short-range structural transformation through long-term structural relaxation.

論文

Observation of field-induced single-ion magnetic anisotropy in a multiorbital Kondo alloy (Lu,Yb)Rh$$_2$$Zn$$_{20}$$

北澤 崇文; 池田 陽一*; 榊原 俊郎*; 松尾 晶*; 清水 悠晴*; 徳永 陽; 芳賀 芳範; 金道 浩一*; 南部 雄亮*; 池内 和彦*; et al.

Physical Review B, 108(8), p.085105_1 - 085105_7, 2023/08

https://doi.org/10.1103/PhysRevB.108.085105

We demonstrate field-induced single-ion magnetic anisotropy resulting from the multiorbital Kondo effect on diluted ytterbium alloy (Lu$$_{1-x}$$Yb$$_x$$)Rh$$_2$$Zn$$_{20}$$. Single-ion anisotropic metamagnetic behavior is revealed in low-temperature regions where the local Fermi-liquid state is formed. Specific heat, low-field magnetic susceptibility, and resistivity indicate reproduction of the ground-state properties by the SU($$N$$ = 8) Kondo model with a relatively large $$c$$-$$f$$ hybridization of $$T_{rm K}$$ = 60.9 K. Dynamical susceptibility measurements on YbRh$$_2$$Zn$$_{20}$$ support realizing multiorbital Kondo ground state in (Lu$$_{1-x}$$Yb$$_x$$)Rh$$_2$$Zn$$_{20}$$. The single-ion magnetic anisotropy becomes evident above $$sim$$5 T, which is lower than the isotropic Kondo crossover field of 22.7 T, verifying blurred low-lying crystal field states through the multiorbital Kondo effect.

論文

Cu $$K$$-edge X-ray absorption fine structure study of $$T'$$-type $$RE$$$$_{2}$$CuO$$_{4+alpha-delta}$$ ($$RE$$ = Rare Earth); Toward unified understanding of electronic state of $$T'$$-type cuprate

Chen, Y.*; 浅野 駿*; Wang, T.*; Xie, P.*; 北山 慎之介*; 石井 賢司*; 松村 大樹; 辻 卓也; 谷口 貴紀*; 藤田 全基*

JPS Conference Proceedings (Internet), 38, p.011050_1 - 011050_6, 2023/05

https://doi.org/10.7566/JPSCP.38.011050

To investigate the variation of the electronic state of $$T'$$-type cuprate due to annealing, we performed Cu $$K$$-edge X-ray absorption fine structure measurements on Pr$$_{2}$$CuO$$_{4+alpha-delta}$$ (PCO) and Pr$$_{1.3}$$La$$_{0.7}$$CuO$$_{4+alpha-delta}$$ (PLCO). The induced electrons due to annealing ($$n_{AN}$$) in PCO and PLCO were approximately 2$$delta$$, consistent with a model of electron doping to Mott insulator. Here, $$alpha$$ and $$delta$$ represent the amount of excess oxygen from the stoichiometric composition in the as-sintered compound and that of oxygen loss due to annealing, respectively. Furthermore, the energy of the Einstein oscillator ($$hbaromega_{E}$$) for the Cu-O$$_{p}$$ bond was evaluated by extended X-ray absorption fine structure analysis. (O$$_{p}$$ denotes the in-plane oxygen.) We found a small annealing effect on $$hbaromega_{E}$$ for both PCO and PLCO.

論文

実建物の47年間の観測による厚肉積層ゴムのクリープ挙動

正木 信男*; 加藤 亨二*; 山本 智彦; 宮川 高行*; 藤田 聡*; 岡村 茂樹*

日本建築学会技術報告集, 28(68), p.81 - 84, 2022/02

https://doi.org/10.3130/aijt.28.81

高速炉等の新型炉では機器の耐震性を確保するため、厚肉積層ゴムの採用が検討されているが、厚肉積層ゴムのもつ柔らかな上下剛性は、経年によるゴム物性の変化とクリープに大きく影響されると考える。われわれはゴム物性の変化を考慮できるクリープ評価方法を検討しているが、参照すべき実大かつ実環境下の長期クリープ特性がない。本報告では、厚肉積層ゴムの新たなクリープ評価方法を検討するための第1段階として、この形式の初めての建物である1966年に竣工した厚肉積層ゴム支持の英国防振建物の測定データを集約し厚肉積層ゴムの約47年間のクリープ特性推定の試みについて述べる。

論文

Spin excitations coupled with lattice and charge dynamics in La$$_{2-x}$$Sr$$_{x}$$CuO$$_{4}$$

池内 和彦*; 脇本 秀一; 藤田 全基*; 福田 竜生; 梶本 亮一; 新井 正敏*

Physical Review B, 105(1), p.014508_1 - 014508_7, 2022/01

https://doi.org/10.1103/PhysRevB.105.014508
 被引用回数：2 パーセンタイル：34.67(Materials Science, Multidisciplinary)

Spin excitations of layered copper oxide show various characteristic features, depending on the carrier concentration. In this paper, we conducted inelastic neutron-scattering measurements on La$$_{2-x}$$Sr$$_{x}$$CuO$$_{4}$$ (LSCO) with $$x$$ = 0, 0.075, 0.18, and 0.30 and La$$_{2-x}$$Sr$$_{x}$$NiO$$_{4}$$ (LSNO) with 1/3 to clarify the origin of the intensity enhancement in the excitation spectrum of LSCO at the energy ($$omega$$) of 16-19 meV [Phys. Rev. B $textbf{91}$, 224404 (2015), $textit{ibid.}$ $textbf{93}$, 094416 (2016)]. We confirmed the presence of a peak structure in the $$omega$$ dependence of the local spin susceptibility $$chi''(omega)$$ of superconducting (SC) LSCO with a peak energy of 16-19 meV where the spin excitations intersect optical phonon branches. A comparable peak structure is not observed in the insulating La$$_{2}$$CuO$$_{4}$$, LSNO, and heavily overdoped LSCO with $$x$$ = 0.30. A dome-shaped $$x$$ dependence of the integrated intensity around the peak energies is revealed for the SC phase by summarizing the present and previously reported results. Furthermore, our phonon calculation on LCO shows the existence of two optical branches at $$sim$$19 meV that could stabilize stripe alignment of carriers due to out-of-plane vibrations of Cu or O of the CuO$$_{2}$$ planes. These results indicate the interplay among spin, charge, and lattice dynamics and suggest that the intensity enhancement is associated with their composite excitations.

論文

Distinct variation of electronic states due to annealing in $$T'$$-type La$$_{1.8}$$Eu$$_{0.2}$$CuO$$_{4}$$ and Nd$$_{2}$$CuO$$_{4}$$

浅野 駿*; 石井 賢司*; 松村 大樹; 辻 卓也; 工藤 康太*; 谷口 貴紀*; 齋藤 真*; 春原 稔樹*; 川股 隆行*; 小池 洋二*; et al.

Physical Review B, 104(21), p.214504_1 - 214504_7, 2021/12

https://doi.org/10.1103/PhysRevB.104.214504
 被引用回数：0 パーセンタイル：0(Materials Science, Multidisciplinary)

We performed Cu K-edge X-ray absorption fine-structure measurements on $$T'$$-type La$$_{1.8}$$Eu$$_{0.2}$$CuO$$_{4}$$ (LECO) and Nd$$_{2}$$CuO$$_{4}$$ (NCO) to investigate the variation in the electronic state associated with the emergence of superconductivity due to annealing. The X-ray absorption near-edge structure spectra of as-sintered (AS) LECO are quite similar to those of AS NCO, indicating that the ground state of AS LECO is a Mott insulator. The electron density after annealing $$n_{rm AN}$$ was evaluated for both superconducting LECO and nonsuperconducting NCO and was found to be 0.40 and 0.05 electron per Cu atom, respectively. In LECO but not in NCO, extended X-ray absorption fine-structure analysis revealed a reduction in the strength of the Cu-O bond in the CuO$$_{2}$$ plane due to annealing, which is consistent with the screening effect on phonons in the metallic state. The origin of the difference in doping processes due to annealing is discussed in relation to the size of the charge-transfer gap.

論文

Triplon current generation in solids

Chen, Y.*; 佐藤 正寛*; Tang, Y.*; 塩見 雄毅*; 大柳 洸一*; 益田 隆嗣*; 南部 雄亮*; 藤田 全基*; 齊藤 英治

Nature Communications (Internet), 12, p.5199_1 - 5199_7, 2021/08

https://doi.org/10.1038/s41467-021-25494-7
 被引用回数：8 パーセンタイル：61.37(Multidisciplinary Sciences)

A triplon refers to a fictitious particle that carries angular momentum $$S=1$$ corresponding to the elementary excitation in a broad class of quantum dimerized spin systems. Such systems without magnetic order have long been studied as a testing ground for quantum properties of spins. Although triplons have been found to play a central role in thermal and magnetic properties in dimerized magnets with singlet correlation, a spin angular momentum flow carried by triplons, a triplon current, has not been detected yet. Here we report spin Seebeck effects induced by a triplon current: triplon spin Seebeck effect, using a spin-Peierls system CuGeO$$_3$$. The result shows that the heating-driven triplon transport induces spin current whose sign is positive, opposite to the spin-wave cases in magnets. The triplon spin Seebeck effect persists far below the spin-Peierls transition temperature, being consistent with a theoretical calculation for triplon spin Seebeck effects.

論文

島原半島北部の唐比低地における湿地堆積物の形成過程

中西 利典*; 奥野 充*; 山崎 圭二*; Hong, W.*; 藤田 奈津子; 中村 俊夫*; 堀川 義之*; 佐藤 鋭一*; 木村 治夫*; 堤 浩之*

名古屋大学年代測定研究,5, p.38 - 43, 2021/03

雲仙火山の約13km西方にある唐比低地には泥炭層や泥層からなる湿地堆積物が厚く分布しており、それらの堆積物には千々石断層や雲仙火山の活動履歴が記録されていることが期待される。それらの履歴を精度よく検知するために、複数本のボーリングコアを掘削して放射性炭素年代値を測定した。それらの結果を地中レーダ探査断面と対比して湿地堆積物の形成過程を検討した。その結果得られたすべての$$^{14}$$C年代値は層序関係と矛盾がなく、堆積曲線は若干のずれが認められるが概ね一致する結果となった。本研究の年代測定の一部はペレトロン年代測定装置による施設供用利用で行われたものである。

論文

Magnetic excitations of Sr$$_{3}$$Ir$$_{2}$$O$$_{7}$$ observed by inelastic neutron scattering technique

藤田 全基*; 池内 和彦*; 梶本 亮一; 中村 充孝

Journal of the Physical Society of Japan, 90(2), p.025001_1 - 025001_2, 2021/02

https://doi.org/10.7566/JPSJ.90.025001
 被引用回数：1 パーセンタイル：16.57(Physics, Multidisciplinary)

In this short note, we report on the first inelastic neutron scattering (INS) study on high-energy magnetic excitations in Sr$$_{3}$$Ir$$_{2}$$O$$_{7}$$. We observed excitations between $$sim$$80 meV and $$sim$$180 meV. The peak position of the excitations is consistent with the dispersion of a single magnon determined by resonant inelastic X-ray scattering (RIXS) measurement. Thus, our results demonstrate the feasibility of INS for iridates, which has a large neutron absorption cross-section.

論文

Coexistence of two components in magnetic excitations of La$$_{2-x}$$Sr$$_{x}$$CuO$$_{4}$$ ($$x$$ = 0.10 and 0.16)

佐藤 研太朗*; 池内 和彦*; 梶本 亮一; 脇本 秀一; 新井 正敏*; 藤田 全基*

Journal of the Physical Society of Japan, 89(11), p.114703_1 - 114703_7, 2020/11

https://doi.org/10.7566/JPSJ.89.114703
 被引用回数：6 パーセンタイル：50.41(Physics, Multidisciplinary)

To elucidate the spin dynamics of La$$_{2-x}$$Sr$$_{x}$$CuO$$_{4}$$, which couples with the charge degree of freedom, the spin excitations spanning the characteristic energy ($$E_mathrm{cross}$$ $$sim$$ 35-40 meV) are investigated for underdoped $$x$$ = 0.10 and optimally doped (OP) $$x$$ = 0.16 through inelastic neutron scattering measurements. Analysis based on a two-component picture of high-quality data clarified the possible coexistence of upright standing incommensurate (IC) excitations with gapless commensurate (C) excitations in the energy-momentum space. The IC component weakens the intensity toward $$E_mathrm{cross}$$ with increasing energy transfer ($$hbaromega$$), whereas the C component strengthens at high-$$hbaromega$$ regions. The analysis results imply that the superposition of two components with a particular intensity balance forms an hourglass-shaped excitation in appearance. Furthermore, the temperature dependence of the intensity of each component exhibits different behaviors; the IC component disappears near the pseudo-gap temperature ($$T^*$$) upon warming, whereas the C component is robust against temperature. These results suggest the itinerant electron spin nature and the localized magnetism of the parent La$$_{2}$$CuO$$_{4}$$ in IC and C excitations, respectively, similar to the spin excitations in the OP YBa$$_{2}$$Cu$$_{3}$$O$$_{6+delta}$$ and HgBa$$_{2}$$CuO$$_{4+delta}$$ with higher superconducting-transition temperatures.

論文

Observation of magnon polarization

南部 雄亮*; Barker, J.*; 沖野 夕貴*; 吉川 貴史*; 塩見 雄毅*; Enderle, M.*; Weber, T.*; Winn, B.*; Graves-Brook, M.*; Tranquada, J. M.*; et al.

Physical Review Letters, 125(2), p.027201_1 - 027201_6, 2020/07

https://doi.org/10.1103/PhysRevLett.125.027201
 被引用回数：45 パーセンタイル：94.07(Physics, Multidisciplinary)

We measure the mode-resolved direction of the precessional motion of the magnetic order, i.e., magnon polarization, via the chiral term of inelastic polarized neutron scattering spectra. The magnon polarization is a unique and unambiguous signature of magnets and is important in spintronics, affecting thermodynamic properties such as the magnitude and sign of the spin Seebeck effect. However, it has never been directly measured in any material until this work. The observation of both signs of magnon polarization in Y$$_3$$Fe$$_5$$O$$_{12}$$ also gives direct proof of its ferrimagnetic nature. The experiments agree very well with atomistic simulations of the scattering cross section.

論文

Crystal structures of highly hole-doped layered perovskite nickelate Pr$$_{2-x}$$Sr$$_{x}$$NiO$$_{4}$$ studied by neutron diffraction

梶本 亮一; 中島 健次; 藤田 全基*; 石角 元志*; 鳥居 周輝*; 石川 喜久*; Miao, P.*; 神山 崇*

Journal of the Physical Society of Japan, 88(11), p.114602_1 - 114602_6, 2019/11

https://doi.org/10.7566/JPSJ.88.114602
 被引用回数：0 パーセンタイル：0(Physics, Multidisciplinary)

A high-resolution time-of-flight powder neutron diffraction study of the layered nickel oxide Pr$$_{2-x}$$Sr$$_{x}$$NiO$$_{4}$$ with $$x = 0.7$$ and $$0.9$$ was performed to characterize the crystal structures of these highly hole-doped nickelates. For the sample with $$x = 0.7$$, the Ni-O bond lengths decrease uniformly with decreasing temperature, and the atomic displacement parameters are similar to those for $$x = 1/3$$. In contrast, for the sample with $$x = 0.9$$, the out-of-plane Ni-O bond length shows a sharp thermal contraction in the high-temperature region, which is suggestive of changes in the orbital occupation accompanied by the development of checkerboard-type charge correlations. Furthermore, the $$x = 0.9$$ sample is characterized by a large atomic displacement parameter for the apical O atoms along the out-of-plane direction, which is interpreted as the existence of two types of Ni$$^{3+}$$ sites with different orbital occupancies. The distinct difference between the $$x = 0.9$$ sample and the lower-concentration compounds should be related to the development of checkerboard-type charge ordering in the metallic matrix and possible orbital ordering at the Ni$$^{3+}$$ sites at $$x sim 1$$ in the hole-doped layered nickel oxides.

論文

Al-impurity-induced magnetic excitations in heavily over-doped La$$_{1.7}$$Sr$$_{0.3}$$Cu$$_{0.95}$$Al$$_{0.05}$$O$$_{4}$$

池内 和彦*; 中島 健次; 河村 聖子; 梶本 亮一; 脇本 秀一; 鈴木 謙介*; 藤田 全基*

AIP Advances (Internet), 8(10), p.101318_1 - 101318_5, 2018/10

https://doi.org/10.1063/1.5043077
 被引用回数：0 パーセンタイル：0(Nanoscience & Nanotechnology)

中性子散乱実験により、Al不純物を導入した実効ホール濃度0.25の銅酸化物超伝導体、La$$_{1.7}$$Sr$$_{0.3}$$Cu$$_{0.95}$$Al$$_{0.05}$$O$$_{4}$$の巨大単結晶について、磁気励起を測定した。

論文

Ce substitution and reduction annealing effects on electronic states in Pr$$_{2-x}$$Ce$$_x$$CuO$$_4$$ studied by Cu $$K$$-edge X-ray absorption spectroscopy

浅野 駿*; 石井 賢司*; 松村 大樹; 辻 卓也; 伊奈 稔哲*; 鈴木 謙介*; 藤田 全基*

Journal of the Physical Society of Japan, 87(9), p.094710_1 - 094710_5, 2018/09

https://doi.org/10.7566/JPSJ.87.094710
 被引用回数：12 パーセンタイル：64.96(Physics, Multidisciplinary)

We investigated the Ce substitution and reduction annealing effects on the electronic states at copper sites by Cu $$K$$-edge X-ray absorption near-edge structure measurements in Pr$$_{2-x}$$Ce$$_x$$CuO$$_{4+alpha-delta}$$ (PCCO) with varying $$x$$ and $$delta$$ (amount of oxygen loss during annealing). Absorption near-edge spectra were modified by Ce substitution and reduction annealing similarly with increasing $$x$$ and $$delta$$. Considering electron doping by Ce substitution, this similarity indicates an increase in electron number at the copper sites due to annealing ($$n_{AN}$$). Furthermore, quantitative analyses of the spectra clarified that the number of Cu$$^+$$ sites, corresponding to the induced electron number by Ce substitution increases linearly with $$x$$ in the as-sintered PCCO, whereas $$n_{AN}$$ is not exactly equal to 2$$delta$$. For each $$x$$-fixed sample, $$n_{AN}$$tends to exceed 2$$delta$$ with increasing $$delta$$, suggesting the emergence of two types of carrier due to annealing.

論文

Instrumental resolution of the chopper spectrometer 4SEASONS evaluated by Monte Carlo simulation

梶本 亮一; 佐藤 研太朗*; 稲村 泰弘; 藤田 全基*

AIP Conference Proceedings 1969, p.050004_1 - 050004_8, 2018/05

https://doi.org/10.1063/1.5039301
 被引用回数：6 パーセンタイル：93.93(Physics, Applied)

We performed simulations of the resolution function of the 4SEASONS spectrometer at J-PARC by using the Monte Carlo simulation package McStas. The simulations showed reasonably good agreement with analytical calculations of energy and momentum resolutions by using a simplified description. We implemented new functionalities in Utsusemi, the standard data analysis tool used in 4SEASONS, to enable visualization of the simulated resolution function and predict its shape for specific experimental configurations.

論文

Detailed study of the structure of the low-energy magnetic excitations in overdoped La$$_{1.75}$$Sr$$_{0.25}$$CuO$$_{4}$$

池内 和彦*; 菊地 龍弥*; 中島 健次; 梶本 亮一; 脇本 秀一; 藤田 全基*

Physica B; Condensed Matter, 536, p.717 - 719, 2018/05

https://doi.org/10.1016/j.physb.2017.11.022
 被引用回数：2 パーセンタイル：10.36(Physics, Condensed Matter)

銅酸化物高温超伝導体の過剰ドープ領域における低エネルギーの磁気励起の構造の詳細を調べるために、我々は、La$$_{1.75}$$Sr$$_{0.25}$$CuO$$_{4}$$の中性子非弾性散乱実験を行った。過去に報告されたように、非整合な磁気相関に対応した$$Q_{rm tet}$$ = (0.5 $$pm$$ $$delta$$, 0.5)/(0.5, 0.5 $$pm$$ $$delta$$)を中心とした磁気励起を明瞭に観測した。それに加えて、$$Q_{rm tet}=(0.5, 0.5)$$を中心とした円環状の励起も観測された。円環の半径($$r$$=0.109)は、磁気相関の非整合性($$delta$$=0.118)より小さい。このことは、円環状の磁気励起は非整合な磁気相関とはその原因を異にしていることを示唆している。La$$_{2-x}$$Sr$$_{x}$$CuO$$_{4}$$の磁気励起はこのように2種類の励起を持つことが示唆される。

論文

Fe-impurity-induced magnetic excitations in heavily over-doped La$$_{1.7}$$Sr$$_{0.3}$$Cu$$_{0.95}$$Fe$$_{0.05}$$O$$_{4}$$

池内 和彦*; 菊地 龍弥*; 中島 健次; 梶本 亮一; 脇本 秀一; 藤田 全基*

Journal of Physics; Conference Series, 969(1), p.012024_1 - 012024_5, 2018/04

https://doi.org/10.1088/1742-6596/969/1/012024
 被引用回数：1 パーセンタイル：52.81(Physics, Applied)

Inelastic neutron scattering experiments were performed to investigate the effect of Fe substitution on the magnetic excitation spectra in a heavily hole-doped cuprate system La$$_{1.7}$$Sr$$_{0.3}$$Cu$$_{0.95}$$Fe$$_{0.05}$$O$$_{4}$$. Well-defined low-energy magnetic excitations, associated with a static magnetic order, were observed at the incommensurate (IC) positions. The incommensurability of 0.144 (r.l.u) was larger than that of $$sim$$0.125 (r.l.u) in LSCO with $$x$$ = 0.25, suggesting an increase of incommensurability by Fe substitution. In addition to the obvious effect on IC excitations, we show the emergence of ring-shaped magnetic excitations by Fe-substitution. These results are incompatible with a simple pinning scenario of the stripe order, which is characterized by local spin correlations. The metallic aspect of the low-energy part of the magnetic excitation, which underlies high-temperature superconductivity in over-doped cuprate systems, would be enhanced/induced by Fe substitution.

論文

Reduction and oxidation annealing effects on Cu $$K$$-edge XAFS for electron-doped cuprate superconductors

浅野 駿*; 鈴木 謙介*; 松村 大樹; 石井 賢司*; 伊奈 稔哲*; 藤田 全基*

Journal of Physics; Conference Series, 969, p.012051_1 - 012051_5, 2018/04

https://doi.org/10.1088/1742-6596/969/1/012051
 被引用回数：3 パーセンタイル：82.15(Physics, Applied)

Reduction and oxidation annealing effects on the electronic states around the copper sites for Pr$$_{2-x}$$Ce$$_x$$CuO$$_4$$ and Nd$$_{2-x}$$Ce$$_x$$CuO$$_4$$ with $$x$$ = 0 and $$x$$ = 0.15 were investigated by Cu $$K$$-edge X-ray absorption measurements. Cu $$K$$ near-edge spectra were changed by the reduction annealing in a manner similar to the case of Ce substitution for both $$x$$ = 0 and $$x$$ = 0.15. This means an increase of electron density at the copper sites, indicating the aspect of electron doping in the reduction annealing. This reduction annealing effect on the near-edge spectra are reverted by the additional oxidation annealing. The amount of electron density around the copper sites is varied by the reduction and oxidation annealing, reversibly, corresponding to the reversible variation of the physical property from insulating to superconductivity.

論文

Materials and Life Science Experimental Facility (MLF) at the Japan Proton Accelerator Research Complex, 2; Neutron scattering instruments

中島 健次; 川北 至信; 伊藤 晋一*; 阿部 淳*; 相澤 一也; 青木 裕之; 遠藤 仁*; 藤田 全基*; 舟越 賢一*; Gong, W.*; et al.

Quantum Beam Science (Internet), 1(3), p.9_1 - 9_59, 2017/12

https://doi.org/10.3390/qubs1030009

J-PARC物質・生命科学実験施設の中性子実験装置についてのレビューである。物質・生命科学実験施設には23の中性子ビームポートがあり21台の装置が設置されている。それらは、J-PARCの高性能な中性子源と最新の技術を組み合わせた世界屈指の実験装置群である。このレビューでは、装置性能や典型的な成果等について概観する。

論文

Observation of momentum-dependent charge excitations in hole-doped cuprates using resonant inelastic X-ray scattering at the oxygen $$K$$ edge

石井 賢司*; 遠山 貴巳*; 浅野 駿*; 佐藤 研太朗*; 藤田 全基*; 脇本 秀一; 筒井 健二*; 曽田 繁利*; 宮脇 淳*; 丹羽 秀治*; et al.

Physical Review B, 96(11), p.115148_1 - 115148_8, 2017/09

AA2017-0402.pdf:0.81MB

https://doi.org/10.1103/PhysRevB.96.115148
 被引用回数：29 パーセンタイル：77.9(Materials Science, Multidisciplinary)

We investigate electronic excitations in La$$_{2-x}$$(Br,Sr)$$_x$$CuO$$_4$$ using resonant inelastic X-ray scattering (RIXS) at the oxygen $$K$$ edge. We observed momentum-dependent spectral weight below 1 eV, which is consistent with theoretical calculation of the dynamical charge structure factor on oxygen orbitals in a three-band Hubbard model. Our results confirm that the momentum-dependent charge excitations exist on the order of the transfer energy ($$t$$), and the broad spectral line shape indicates damped and incoherent character of the charge excitations at the energy range in the doped Mott insulators.

157 件中 1件目～20件目を表示