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 ...

発表言語

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

Structural behaviors of lead zirconate titanate-based ferroelectric ceramics during pyroelectric-power generation cycles

川崎 卓郎; 福田 竜生; 山中 暁*; 村山 一郎*; 加藤 孝典*; 馬場 将亮*; 橋本 英樹*; Harjo, S.; 相澤 一也; 田中 裕久*; et al.

Journal of Applied Physics, 137(9), p.094101_1 - 094101_7, 2025/03

https://doi.org/10.1063/5.0243081
 被引用回数：0 パーセンタイル：0.00(Physics, Applied)

Energy harvesting from waste heat can improve energy efficiency in society. This research investigated the structural behaviors of lead zirconate titanate-based ferroelectric ceramics using operando neutron diffraction measurements under the conditions of two energy-harvesting cycles that involve consideration of the temperature changes of automobile exhaust gas for achieving good harvesting efficiencies. Input and output electrical energies and neutron diffraction data were simultaneously collected. The obtained time-resolved neutron-diffraction intensity data indicate that the applied electric fields and temperature changes induced 90$$^{circ}$$ domain rotation and lattice strain. These structural changes and their variations depending on cycle conditions, such as temperature changes, applied electric fields, and circuit switching, provide insight into the origins of the differences in the behaviors of electrical input/output energies in the cycles.

論文

Surface and interfacial aggregation states in thin films of a polystyrene/polyrotaxane blend

田口 美岐*; 宮田 登*; 宮崎 司*; 青木 裕之; Ozawa, Satoru*; 長谷川 龍一 *; 盛満 裕真*; 川口 大輔*; 山本 悟*; 田中 敬二*

Polymer Journal, 7 Pages, 2025/03

https://doi.org/10.1038/s41428-025-01030-y
 被引用回数：0 パーセンタイル：0.00(Polymer Science)

Polyrotaxane (PR) exhibits unique mechanical properties due to the ability of its cyclic molecules to move or slide along the axial chain. Thus, to design advanced polymer-based composite materials and organic devices, it is crucial to better understand the aggregation states at the surface and substrate interface in polymer films containing PR. Here, we report the depth profile of PR along the direction normal to the interface when it is mixed with polystyrene (PS). Neutron reflectivity and X-ray photoelectron spectroscopy revealed that PS and PR segregated at the surface and substrate interface, respectively, and that the extent of segregation depended on the length of PS. The surface enrichment of PS is driven by both energy and entropy, whereas the enrichment of PR at the substrate interface is energy driven.

論文

In-plane movement of isolated poly(methacrylate) chains on a hydrophilic solid surface

Kawano, Masayuki*; 盛満 裕真*; Liu, Y.*; 宮田 登*; 宮崎 司*; 青木 裕之; 川口 大輔*; 山本 悟*; 田中 敬二*

Macromolecules, 57(14), p.6625 - 6633, 2024/07

https://doi.org/10.1021/acs.macromol.4c00724
 被引用回数：0 パーセンタイル：0.00(Polymer Science)

A better understanding of the dynamic behavior of polymer chains on solid surfaces is indispensable for the design and construction of high-performance polymer composites. We herein visualized the in-plane movement of isolated poly(methyl methacrylate) (PMMA) and poly(tert-butyl methacrylate) (PtBMA) single chains on hydrophilic silicon wafers under ambient conditions by atomic force microscopy. Isolated PMMA chains adsorbed to the substrate, whereas PtBMA chains diffused, the degree of which was dependent on the humidity. Neutron reflectivity revealed the formation of a layer of condensed water on the substrate. All-atomistic molecular dynamics simulations implied that the diffusivity difference of the two polymers was based on the submerged depth in which a part of a chain existed. That is, the interaction of a polymer with the surface of the hydrophilic substrate primarily governs its lateral movement, or adsorption behavior, facilitated by the presence of water.

論文

Polarization dependence of soft X-ray absorption spectroscopy on the heavy fermion superconductor CeNi$$_{2}$$Ge$$_{2}$$

藤原 秀紀*; 中谷 泰博*; 荒谷 秀和*; 金井 惟奈*; 山神 光平*; 濱本 諭*; 木須 孝幸*; 関山 明*; 田中 新*; 海老原 孝雄*; et al.

New Physics; Sae Mulli, 73(12), p.1062 - 1066, 2023/12

https://doi.org/10.3938/NPSM.73.1062

We have performed soft X-ray absorption spectroscopy (XAS) on the heavy fermion superconductor CeNi$$_{2}$$Ge$$_{2}$$ to examine the local 4${it f}$ electronic structure. The XAS spectra are qualitatively explained by ionic calculations, indicating a degree of localized character of the 4${it f}$ states, while sizable ${it cf}$-hybridization effects are also observed in the XAS spectra and those magnetic circular dichroism. In addition, the temperature dependence of linear dichroism in the XAS spectra indicates that the ground state symmetry is $$Gamma$$$$_{7}$$, and the excited states with $$Gamma$$$$_{6}$$ symmetry is above 390 K.

論文

Impact of the ground-state 4${it f}$ symmetry for anisotropic ${it cf}$ hybridization in the heavy-fermion superconductor CeNi$$_{2}$$Ge$$_{2}$$

藤原 秀紀*; 中谷 泰博*; 荒谷 秀和*; 金井 惟奈*; 山神 光平*; 濱本 諭*; 木須 孝幸*; 山崎 篤志*; 東谷 篤志*; 今田 真*; et al.

Physical Review B, 108(16), p.165121_1 - 165121_10, 2023/10

https://doi.org/10.1103/PhysRevB.108.165121
 被引用回数：0 パーセンタイル：0.00(Materials Science, Multidisciplinary)

We report the ground-state symmetry of the Ce 4${it f}$ states in the heavy-fermion superconductor CeNi$$_{2}$$Ge$$_{2}$$, yielding anisotropic ${it cf}$ hybridization between the Ce 4${it f}$ states and conducting electrons. By analyzing linear dichroism in soft X-ray absorption and core-level hard X-ray photoemission spectra, the 4${it f}$ symmetry is determined as $$Sigma$$-type $$Gamma$$$$_{7}$$, promoting predominant hybridization with the conducting electrons originating from the Ge site. The band structures probed by soft X-ray angle-resolved photoemission indicates that the Ge 4${it p}$ components contribute to the band renormalization through the anisotropic hybridization effects, suggesting that the control of the electronic structures of Ge orbital gives an impact to achieve the exotic phenomena in CeNi$$_{2}$$Ge$$_{2}$$.

論文

Kinetics of the interfacial curing reaction for an epoxy-amine mixture

Yamaguchi, Ko*; 川口 大輔*; 宮田 登*; 宮崎 司*; 青木 裕之; 山本 悟*; 田中 敬二*

Physical Chemistry Chemical Physics, 24(36), p.21578 - 21582, 2022/09

https://doi.org/10.1039/D2CP03394A
 被引用回数：12 パーセンタイル：79.91(Chemistry, Physical)

A better understanding of the chemical reaction between epoxy and amine compounds at a solid interface is crucial for the design and fabrication of materials with appropriate adhesive strength. Here, we examined the curing reaction kinetics of epoxy phenol novolac and 4,4'-diaminodiphenyl sulfone at the outermost interface using sum-frequency generation spectroscopy, and X-ray and neutron reflectivity in conjunction with a full atomistic molecular dynamics simulation. The reaction rate constant was much larger at the quartz interface than in the bulk. While the apparent activation energy at the quartz interface obtained from an Arrhenius plot was almost identical to the bulk value, the frequency factor at the quartz interface was greater than that in the bulk. These results could be explained in terms of the densification and orientation of reactants at the interface, facilitating the encounter of the reactants present.

論文

Fabrication of (Bi$$_2$$)$$_m$$(Bi$$_2$$Te$$_3$$)$$_n$$ superlattice films by Te desorption from a pristine Bi$$_2$$Te$$_3$$ film

日下 翔太郎*; 佐々木 泰祐*; 角田 一樹; 一ノ倉 聖*; 出田 真一郎*; 田中 清尚*; 宝野 和博*; 平原 徹*

Applied Physics Letters, 120(17), p.173102_1 - 173102_5, 2022/04

https://doi.org/10.1063/5.0090207
 被引用回数：4 パーセンタイル：35.53(Physics, Applied)

We fabricated superlattice films composed of Bi$$_2$$ bilayers (BLs) and Bi$$_2$$Te$$_3$$ quintuple layers (QLs) by annealing pure Bi$$_2$$Te$$_3$$ films. It was found that Te desorbs from the QL to form the BL with an activation energy of 2.7 eV. Eventually two distinct stoichiometric phases were formed, Bi$$_1$$Te$$_1$$ (QL-BL-QL) and Bi$$_4$$Te$$_3$$ (QL-BL), as evidenced by scanning transmission emission microscopy measurements. The surface-state dispersion was measured with angle-resolved photoemission spectroscopy and the topological nature of each sample is discussed. Our method offers a convenient and simple way to fabricate superlattice films with different topological properties.

論文

${it Operando}$ structure observation of pyroelectric ceramics during power generation cycle

川崎 卓郎; 福田 竜生; 山中 暁*; 坂本 友和*; 村山 一郎*; 加藤 孝典*; 馬場 将亮*; 橋本 英樹*; Harjo, S.; 相澤 一也; et al.

Journal of Applied Physics, 131(13), p.134103_1 - 134103_7, 2022/04

https://doi.org/10.1063/5.0084166
 被引用回数：2 パーセンタイル：16.92(Physics, Applied)

The microscopic origin of the pyroelectric power generation using ferroelectric ceramics for energy harvesting from time-varying waste heat can be understood by conducting ${it operando}$ neutron diffraction measurements. The behavior of the domain orientation and lattice strain in the lead zirconate titanate (PZT)-based ceramics with a tetragonal structure during the novel power generation cycle combining electric field and temperature change were investigated. The [001] domains and the lattice strain of the (111) plane in the direction of parallel to the electric field increase in the process of simultaneous rise in the electric field and temperature, and rapidly decrease in the process of the field drop. The alignment of the domain orientation by the electric field and its randomization by the higher temperature during the cycle are critical features of the current power generation system.

論文

Environmental effects on layer-dependent dynamics of Dirac fermions in quasicrystalline bilayer graphene

Zhao, Y.*; Suzuki, T.*; Iimori, T.*; Kim, H.-W.*; Ahn, J. R.*; 堀尾 眞史*; 佐藤 祐輔*; 深谷 有喜; Kanai, T.*; Okazaki, K.*; et al.

Physical Review B, 105(11), p.115304_1 - 115304_8, 2022/03

https://doi.org/10.1103/PhysRevB.105.115304
 被引用回数：1 パーセンタイル：7.68(Materials Science, Multidisciplinary)

本研究では、時間・角度分解光電子分光を用いて、SiC基板上に作製したグラフェン層におけるキャリアダイナミクスについて調べた。光ポンピング後の準結晶グラフェンのディラックバンドでは、電子ドーピングに層依存性が観測された。また、光誘起キャリア輸送量は基板からの距離に依存することがわかった。フラット基板及びステップ基板上の単層グラフェンの結果から、キャリアの生成源は界面のステップ状態に由来することがわかった。本メカニズムは、密度汎関数計算による電子構造を基にした動的モデルにより記述できる。

論文

Dynamics of radiocaesium within forests in Fukushima; Results and analysis of a model inter-comparison

橋本 昌司*; 田中 拓*; 小松 雅史*; Gonze, M.-A.*; 坂下 渉*; 操上 広志; 仁科 一哉*; 太田 雅和; 大橋 伸太*; Calmon, P.*; et al.

Journal of Environmental Radioactivity, 238-239, p.106721_1 - 106721_10, 2021/11

https://doi.org/10.1016/j.jenvrad.2021.106721
 被引用回数：14 パーセンタイル：57.65(Environmental Sciences)

本研究は、福島の主に常緑針葉樹林内における放射性セシウムの移行について、複数の研究チームによるモデルを用いた解析を行い、比較を行うことで、モデルのパフォーマンスを分析したものである。また、落葉層の除去と樹木更新の2つの管理シナリオ、および落葉広葉樹林を対象とした補助シナリオについても比較、分析した。いずれのモデルも実測の放射性セシウム濃度の変化傾向などを再現できたが、事故から50年後の予測についてはばらつきが大きく、継続した調査、解析による評価が必要である。

論文

Absence of ferromagnetism in MnBi$$_2$$Te$$_4$$/Bi$$_2$$Te$$_3$$ down to 6 K

深澤 拓朗*; 日下 翔太郎*; 角田 一樹; 橋爪 瑞葵*; 一ノ倉 聖*; 竹田 幸治; 出田 真一郎*; 田中 清尚*; 清水 亮太*; 一杉 太郎*; et al.

Physical Review B, 103(20), p.205405_1 - 205405_6, 2021/05

https://doi.org/10.1103/PhysRevB.103.205405
 被引用回数：9 パーセンタイル：52.33(Materials Science, Multidisciplinary)

We successfully fabricated a MnBi$$_2$$Te$$_4$$/Bi$$_2$$Te$$_3$$ heterostructure by incorporating Mn and Te inside the topmost quintuple layer of Bi$$_2$$Te$$_3$$, as unambiguously confirmed by LEED I-V scanning transmission electron microscopy measurements. The surface-state Dirac cone of the heterostructure showed little change compared to that of the pristine Bi$$_2$$Te$$_3$$ and X-ray magnetic circular dichroism measurements showed that the system was paramagnetic down to 5.6 K. These results are in contrast to the previous works on related materials that showed magnetic order around 10 K as well as theoretical predictions and suggests the intricacy of the magnetic properties of two-dimensional van der Waals magnets.

論文

Thermally altered subsurface material of asteroid (162173) Ryugu

北里 宏平*; Milliken, R. E.*; 岩田 隆浩*; 安部 正真*; 大竹 真紀子*; 松浦 周二*; 高木 靖彦*; 中村 智樹*; 廣井 孝弘*; 松岡 萌*; et al.

Nature Astronomy (Internet), 5(3), p.246 - 250, 2021/03

https://doi.org/10.1038/s41550-020-01271-2
 被引用回数：57 パーセンタイル：96.00(Astronomy & Astrophysics)

2019年4月「はやぶさ2」ミッションは、地球に近い炭素質の小惑星(162173)リュウグウの人工衝撃実験を成功させた。これは露出した地下物質を調査し、放射加熱の潜在的な影響をテストする機会を提供した。はやぶさ2の近赤外線分光器(NIRS3)によるリュウグウの地下物質の観測結果を報告する。発掘された材料の反射スペクトルは、表面で観測されたものと比較して、わずかに強くピークがシフトした水酸基(OH)の吸収を示す。これは、宇宙風化や放射加熱が最上部の表面で微妙なスペクトル変化を引き起こしたことを示している。ただし、このOH吸収の強度と形状は、表面と同様に、地下物質が300$$^{circ}$$Cを超える加熱を経験したことを示している。一方、熱物理モデリングでは、軌道長半径が0.344AUに減少しても、推定される掘削深度1mでは放射加熱によって温度が200$$^{circ}$$Cを超えて上昇しないことが示されている。これは、リュウグウ母天体が放射加熱と衝撃加熱のいずれか、もしくは両方により熱変化が発生したという仮説を裏付けている。

論文

High temperature gas-cooled reactors

武田 哲明*; 稲垣 嘉之; 相原 純; 青木 健; 藤原 佑輔; 深谷 裕司; 後藤 実; Ho, H. Q.; 飯垣 和彦; 今井 良行; et al.

High Temperature Gas-Cooled Reactors; JSME Series in Thermal and Nuclear Power Generation, Vol.5, 464 Pages, 2021/02

https://doi.org/10.1016/C2018-0-05383-9

本書は、原子力機構における今までの高温ガス炉の研究開発の総括として、HTTRの設計、燃料、炉内構造物や中間熱交換器などの要素技術の開発、出力上昇試験、950$$^{circ}$$Cの高温運転、安全性実証試験などの運転経験及び成果についてまとめたものである。また、HTTRでの知見をもとに、商用炉の設計、高性能燃料、ヘリウムガスタービン、ISプロセスによる水素製造などの要素技術開発の現状について記述しており、今後の高温ガス炉の開発に非常に有用である。本書は、日本機械学会の動力エネルギーシステム部門による化石燃料及び原子力によるエネルギーシステムの技術書のシリーズの一冊として刊行されるものである。

論文

Synchronized gravitational slope deformation and active faulting; A Case study on and around the Neodani fault, central Japan

小村 慶太朗*; 金田 平太郎*; 田中 知季*; 小嶋 智*; 井上 勉*; 西尾 智博

Geomorphology, 365, p.107214_1 - 107214_22, 2020/09

https://doi.org/10.1016/j.geomorph.2020.107214
 被引用回数：4 パーセンタイル：26.87(Geography, Physical)

本研究では、岐阜・福井県境の重力変形地形と、近接する根尾谷断層上で掘削調査を実施した。その結果、重力変形地形では少なくとも4回の成長イベントが検出され、それぞれの年代が240cal BP以降、1710-340cal BP、4730-3970cal BP、5570-5340cal BPに絞り込まれた。一方、根尾谷断層本体でも少なくとも計4回の古地震イベントが明らかとなり、それぞれの年代が新しいものから1891年濃尾地震、2010-1220cal BP、7180-2110cal BP、9540cal BPと推定され、本研究では重力変形地形のイベントが毎回根尾谷断層の活動に誘発されているものと結論付けた。また、クーロン応力変化のモデリングによると、本研究地域は根尾谷断層の活動により正断層運動が著しく促進されることが明らかとなった。従来、地震に伴う大規模地滑りや重力変形は地震動のみで論じられることが多かったが、本研究地域のように活断層のごく近傍では、地震動だけでなく、断層運動による地殻の静的歪みが重力変形の発生・成長に大きな影響を与えている可能性がある。

論文

Fabrication of a novel magnetic topological heterostructure and temperature evolution of its massive Dirac cone

平原 徹*; Otrokov, M. M.*; 佐々木 泰祐*; 角田 一樹*; 友弘 雄太*; 日下 翔太郎*; 奥山 裕磨*; 一ノ倉 聖*; 小林 正起*; 竹田 幸治; et al.

Nature Communications (Internet), 11, p.4821_1 - 4821_8, 2020/09

https://doi.org/10.1038/s41467-020-18645-9
 被引用回数：50 パーセンタイル：90.49(Multidisciplinary Sciences)

We fabricate a novel magnetic topological heterostructure Mn$$_{4}$$Bi$$_{2}$$Te$$_{7}$$/Bi$$_{2}$$Te$$_{3}$$ where multiple magnetic layers are inserted into the topmost quintuple layer of the original topological insulator Bi$$_{2}$$Te$$_{3}$$. A massive Dirac cone (DC) with a gap of 40-75 meV at 16 K is observed. By tracing the temperature evolution, this gap is shown to gradually decrease with increasing temperature and a blunt transition from a massive to a massless DC occurs around 200-250 K. Magnetic measurements show that there are two distinct Mn components in the system that corresponds to the two heterostructures; MnBi$$_{2}$$Te$$_{4}$$/Bi$$_{2}$$Te$$_{3}$$ is paramagnetic at 6 K while Mn$$_{4}$$Bi$$_{2}$$Te$$_{7}$$/Bi$$_{2}$$Te$$_{3}$$ is ferromagnetic with a negative hysteresis (critical temperature 20 K). This novel heterostructure is potentially important for future device applications.

論文

Pyroelectric power generation from the waste heat of automotive exhaust gas

Kim, J.*; 山中 暁*; 村山 一郎*; 加藤 孝典*; 坂本 友和*; 川崎 卓郎; 福田 竜生; 関野 徹*; 中山 忠親*; 武田 雅敏*; et al.

Sustainable Energy & Fuels (Internet), 4(3), p.1143 - 1149, 2020/03

https://doi.org/10.1039/C9SE00283A
 被引用回数：21 パーセンタイル：64.56(Chemistry, Physical)

Waste heat is a potentially exploitable energy source but remains a problem awaiting a solution. To explore solutions for automobile applications, we investigate pyroelectric power generation from the temperature variation of exhaust gas using a novel electro-thermodynamic cycle. Niobium-doped lead zirconate titanate stannate (PNZST) ceramics were applied as pyroelectric materials, and their structural characteristics were investigated. In the driving cycle assessments (JC-08) using real exhaust gas, the maximum power generated was identified as 143.9 mW cm$$^{-3}$$ (777.3 J L$$^{-1}$$ per 1 cycle) over a temperature range of 150-220 $$^{circ}$$C and an electric field of 13 kV cm-1. The net mean generating power of the total driving cycle was 40.8 mW cm$$^{-3}$$, which is the most enhanced result in our power generating systems to date and 314 times greater than our first report. Materials with sharp transition behaviors with the temperature and electric field are worthy of study with regard to pyroelectric energy harvesting materials, and their corresponding crystal and domain structures were investigated to optimize performance.

論文

The Surface composition of asteroid 162173 Ryugu from Hayabusa2 near-infrared spectroscopy

北里 宏平*; Milliken, R. E.*; 岩田 隆浩*; 安部 正真*; 大竹 真紀子*; 松浦 周二*; 荒井 武彦*; 仲内 悠祐*; 中村 智樹*; 松岡 萌*; et al.

Science, 364(6437), p.272 - 275, 2019/04

https://doi.org/10.1126/science.aav7432
 被引用回数：294 パーセンタイル：99.68(Multidisciplinary Sciences)

小惑星探査機はやぶさ2のターゲット天体であるリュウグウは、始原的な炭素質物質で構成されていると考えられている。はやぶさ2に搭載された近赤外分光計(NIRS3)によって、天体の表面組成を得た。天体全体の観測で、弱く細い吸収が2.72ミクロンに確認され、OHを含む鉱物の存在を示している。弱いOH吸収と低いアルベドは熱やショックによって変質を受けた炭素質コンドライトに似ている。OHバンドの位置はほとんど一定であり、衝撃片の集合によって形成されたリュウグウは組成的に均質であることを示している。

論文

Electrical and crystallographic study of an electrothermodynamic cycle for a waste heat recovery

Kim, J.*; 山中 暁*; 中島 啓*; 加藤 孝典*; Kim, Y.*; 福田 竜生; 吉井 賢資; 西畑 保雄; 馬場 将亮*; 武田 雅敏*; et al.

Advanced Sustainable Systems (Internet), 2(11), p.1800067_1 - 1800067_8, 2018/11

https://doi.org/10.1002/adsu.201800067
 被引用回数：8 パーセンタイル：27.18(Green & Sustainable Science & Technology)

An innovative electrothermodynamic cycle (pyroelectric effect with an external electric field) was recently presented, which is based on temporal temperature variations in wasted heat from engine exhaust gas. In this paper, for further improvement, a generating mechanism of the cycle is investigated using in-operando time-resolved synchrotron X-ray diffraction with generating assessment. The polarizations of the sample are gained from both crystal/domain changes and simultaneous electrical measurements. Three types of materials are prepared: soft and hard types of lead zirconate titanate (PZT) and lead magnesium niobate-lead titanate (PMN-PT). Among them, PMN-PT has the highest generating power. When an external electric field is applied, the PMN-PT exhibits only 180$$^circ$$ domain rotations, whereas PZTs exhibit both 90$$^circ$$ and 180$$^circ$$ rotations. A strong driving force for 180$$^circ$$ rotation depresses rotations in other angles and increases polarization changes. The results show that the material development, which has only 180$$^circ$$ switching domains, has potential for use in the establishment of a high-efficiency waste heat recovery system.

論文

Temperature stability of PIN-PMN-PT ternary ceramics during pyroelectric power generation

茂呂 拓哉*; Kim, J.*; 山中 暁*; 村山 一郎*; 加藤 孝典*; 中山 忠親*; 武田 雅敏*; 山田 昇*; 西畑 保雄; 福田 竜生; et al.

Journal of Alloys and Compounds, 768, p.22 - 27, 2018/11

https://doi.org/10.1016/j.jallcom.2018.07.182
 被引用回数：18 パーセンタイル：61.88(Chemistry, Physical)

Relaxor-based ternary Pb(In$$_{1/2}$$Nb$$_{1/2}$$)O$$_3$$-Pb(Mg$$_{1/3}$$Nb$$_{2/3}$$)O$$_3$$-PbTiO$$_3$$ (PIN-PMN-PT) ceramics near a morphotropic phase boundary were grown, and their electrical properties at various temperatures were investigated in the electrothermodynamic cycle for the future environment-friendly automotive applications. Structural disordering, depending on the PIN content, influenced the diffuse phase transition between the tetragonal and cubic structures and contributed to the power-generating behavior. The net power-generating energies (P$$_{net}$$) were 2.43-3.01 mW/cm$$^3$$ at temperatures above 200$$^circ$$C and were maintained at above 1 mW/cm$$^3$$ over a temperature range of approximately 100 degrees. Therefore, the PIN-PMN-PT system has a possibility of a wider usage temperature range, the disordering of the perovskite crystal structure can be controlled, and it will be a candidate for the application of pyroelectric energy conversion system.

論文

Revising the 4${it f}$ symmetry in CeCu$$_{2}$$Ge$$_{2}$$; Soft X-ray absorption and hard X-ray photoemission spectroscopy

荒谷 秀和*; 中谷 泰博*; 藤原 秀紀*; 川田 萌樹*; 金井 惟奈*; 山神 光平*; 藤岡 修平*; 濱本 諭*; 久我 健太郎*; 木須 孝幸*; et al.

Physical Review B, 98(12), p.121113_1 - 121113_6, 2018/09

AA2018-0352.pdf:1.16MB

https://doi.org/10.1103/PhysRevB.98.121113
 被引用回数：5 パーセンタイル：22.62(Materials Science, Multidisciplinary)

We present a detailed study on the $$4f$$ ground state symmetry of the pressure-induced superconductor CeCu$$_2$$Ge$$_2$$ probed by soft X-ray absorption and hard X-ray photoemission spectroscopy. The revised Ce $$4f$$ ground states are determined as $$|{Gamma_7}rangle=sqrt{0.45}|{J_{z}=pm frac{5}{2}}rangle - sqrt{0.55}|{mp frac{3}{2}}rangle$$ with $$Sigmamathchar`-{rm type}$$ in-plane rotational symmetry. This gives an in-plane magnetic moment consistent with the antiferromagnetic moment as reported in neutron measurements. Since the in-plane symmetry is the same as that for the superconductor CeCu$$_2$$Si$$_2$$, we propose that the charge distribution along the $$c$$-axis plays an essential role in driving the system into a superconducting phase.

157 件中 1件目～20件目を表示