2025/03/17 更新

写真a

ホリデ トモヤ
堀出 朋哉
HORIDE Tomoya
所属
大学院工学研究科 電気工学専攻 先端エネルギー 准教授
大学院担当
大学院工学研究科
学部担当
工学部 電気電子情報工学科
職名
准教授

学位 1

  1. 博士(工学) ( 2008年3月   京都大学 ) 

 

論文 20

  1. Monte Carlo Study on Crystal Growth of BMO-Doped REBCO Films Affected by Growth Conditions

    Ichino, Y; Arita, T; Seike, Y; Taoka, N; Mori, T; Horio, K; Ichinose, A; Horide, T; Matsumoto, K; Yoshida, Y

    IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY   35 巻 ( 5 )   2025年8月

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    出版者・発行元:IEEE Transactions on Applied Superconductivity  

    This study investigates the formation of BaMO3 (BMO) nanostructures in REBa2Cu3Oy(REBCO) thin films using Monte Carlo simulations. We explored the effects of deposition conditions, particularly high deposition rates, on nanostructure morphology. Our simulations demonstrate that straight BMO nanorods can form even under rapid deposition when substrate temperature and BMO content are sufficiently high. We employed Bayesian optimization to refine simulation parameters, improving the agreement between simulated and experimental crystal grain densities. While full concordance was not achieved, this approach shows promise for future refinements. Our findings provide insights into artificial pinning center design in REBCO superconducting wires and underscore the potential of combining simulation and optimization techniques in materials science research.

    DOI: 10.1109/TASC.2024.3512529

    Web of Science

    Scopus

  2. Effect of Oxygen Annealing on RE123 Superconducting Film Inferred From Changes in Microstructure

    Ichinose, A; Yamazaki, S; Matsumoto, K; Ichino, Y; Horio, K; Horide, T; Yoshida, Y

    IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY   35 巻 ( 5 )   2025年8月

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    出版者・発行元:IEEE Transactions on Applied Superconductivity  

    Coated conductors are actively manufactured by several wire companies around the worldwide to fabricate high-field magnets. The critical temperature of RE123 superconductors, used in these coated conductors, is significantly influenced by oxygen annealing during manufacturing. Recent observation of the microstructure in oxygen post-annealed and as-deposited films, fabricated via pulsed laser deposition, revealed significant differences in oxygen content and microstructural characteristics. Bayesian optimization was used to generate a two-dimensional map of annealing parameters for determining the optimal annealing temperature and duration in an oxygen atmosphere. This study presents the results of transmission electron microscopy observations of the microstructure in superconducting films deposited under various conditions identified on the map. The findings also infer the effect of oxygen annealing on microstructural changes.

    DOI: 10.1109/TASC.2024.3523253

    Web of Science

    Scopus

  3. Asymmetric self-organization from a symmetric film by phase separation Open Access

    Horide, T; Usuki, M; Ishimaru, M; Horibe, Y

    NANOSCALE   17 巻 ( 8 ) 頁: 4740 - 4749   2025年2月

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    記述言語:英語   出版者・発行元:Nanoscale  

    Self-organization realizes various nanostructures to control material properties such as superconducting vortex pinning and thermal conductivity. However, the self-organization of nucleation and growth is constrained by the growth geometric symmetry. To realize highly controlled three-dimensional nanostructures by self-organization, nanostructure formation that breaks the growth geometric symmetry thermodynamically and kinetically, such as tilted or in-plane aligned nanostructures, is a challenging issue. A vertically aligned nano-checkerboard is typically formed from ZnMnGaO4 with the twin domain vertically aligned by the stress from the MgO substrate. The change in the template structure is promising to form a different type of nanostructure. The cubic ZnMnGaO4/MgO films were annealed to form nanoscale tetragonal domains in the tilted direction from the surface, which is determined by lattice mismatch, lattice symmetry, and atomic bonding. On the other hand, as a result of free deformation, in-plane aligned twin domains were formed on the SrTiO3 substrate with a thin MgO buffer layer, which does not induce stress in the ZnMnGaO4 film. By annealing the ZnMnGaO4/MgO/SrTiO3 film, the nano-checkerboard with a size of ∼10 nm and a length of ∼200 nm is elongated to the in-plane [100] or [001] direction. This study demonstrates the possibility of fabricating a nanostructure that breaks the growth geometric symmetry, which is not achieved by the previous self-organization. The phase separation with controlled template opens more complicated three-dimensional structures by self-organization.

    DOI: 10.1039/d4nr04343j

    Open Access

    Web of Science

    Scopus

    PubMed

  4. Monte Carlo simulation study on BaMO<sub>3</sub> nanostructures in BMO-doped REBa<sub>2</sub>Cu<sub>3</sub>O<sub><i>y</i> </sub> thin films prepared by the vapor-liquid-solid technique

    Arita, T; Ichino, Y; Horide, T; Yoshida, Y

    JAPANESE JOURNAL OF APPLIED PHYSICS   63 巻 ( 10 )   2024年10月

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    出版者・発行元:Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers  

    In depositing REBa2Cu3Oy (REBCO) superconducting thin films, the vapor-liquid-solid (VLS) technique offers advantages over usual pulsed laser deposition (PLD) for achieving high deposition rates and controlled crystal orientation. However, introducing BaMO3 (BMO) additions into VLS-REBCO thin films to enhance critical current density in magnetic fields can lead to distinct nanostructures compared to films prepared by PLD. While simulations have explored nanorod morphologies in PLD. However, a comprehensive understanding of BMO nanostructure self-organization in VLS growth remains elusive. This study presents a novel simulation approach that incorporates the liquid phase as droplets and motion of them within the VLS process. This model successfully reproduces experimental observed BMO nanostructures in VLS growth, providing valuable insights and a practical guideline for tailoring BMO nanostructures using the VLS technique.

    DOI: 10.35848/1347-4065/ad7f39

    Web of Science

    Scopus

  5. Tc and resistivity variation induced by external bending strain in flexible film of strain-sensitive (La, Sr)<sub>2</sub>CuO<sub>4</sub> 査読有り 国際誌

    Horide, T; Maekawa, T; Aikawa, T; Kitamura, T; Nakamura, K

    PHYSICAL REVIEW MATERIALS   8 巻 ( 9 )   2024年9月

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    記述言語:英語   出版者・発行元:Physical Review Materials  

    Strain in materials changes their electronic structure, and the strain response realizes rich material properties and devices. Superconductivity under hydrostatic pressure and epitaxial strain suggests significant response to an external variable strain in a single sample, but this has not yet been demonstrated because the strain is usually a fixed parameter after sample fabrication. (La,Sr)2CuO4 films were fabricated on flexible metal substrates, and bending strain was applied to them to observe the critical temperature (Tc) and resistivity variation induced by strain. The compressive bending strain of -0.005 increased the Tc from 23.4 to 27.3 K. The magnitude of the Tc change by the bending strain is independent of the doping level and initial epitaxial strain. Furthermore, the irreversibility temperature was also improved by the compressive bending, and reasonable Tc variation with respect to the reversible strain was observed. Ab initio density functional calculation for the mother compound La2CuO4 clarified that the low-energy electronic structures are sensitive to the bending strain. While the carriers (holes) are preferentially injected into the in-plane orbitals of the CuO2 plane under the compressive strain, the tensile strain leads to the carrier injection into the perpendicular orbitals which is unfavorable to the superconductivity. The strain-sensitive high-Tc superconductor under the external strain highlights a new aspect for cuprate superconductors, which opens monitoring of the stress situation in the cryogenic systems such as superconducting magnet and liquid hydrogen container.

    DOI: 10.1103/PhysRevMaterials.8.094802

    Web of Science

    Scopus

  6. データ科学, 計算科学, 実験的手法を活用した超電導物質探索と設計

    堀出 朋哉, 伊豫 彰, 一野 祐亮

    電気学会論文誌. A   144 巻 ( 9 ) 頁: 344 - 349   2024年9月

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    担当区分:責任著者   記述言語:日本語   出版者・発行元:一般社団法人 電気学会  

    The discovery of new superconductors has a significant impact on the scientific and engineering communities, unraveling interesting physical phenomena and providing unique applications in energy and devices. Superconductors with a high critical temperature are limited to a few families, such as cuprates, iron-based compounds, and hydrides under ultra-high pressure. In traditional studies, the exploration of new superconductors relies on theories, experiments, and simulations. However, recent advances in data science have made machine learning available in a variety of fields, including materials informatics. Utilizing superconductor databases and various regression methods, machine learning has proposed several new superconductors. The chemical descriptors are widely used, and the descriptor of the crystalline structure is being developed for more accurate prediction. In this review, the theoretical and experimental studies for the discovery of new superconductors are explained. The available database and data-driven studies are also shown. Furthermore, after reviewing the recent machine learning studies for the discovery of new superconductors and other materials, future aspects in this field are discussed.

    DOI: 10.1541/ieejfms.144.344

    Scopus

    CiNii Research

  7. Suppression of grain boundary weak link by Ca doping in YBa2Cu3O7 coated conductor 査読有り

    Yamamoto, K; Yoshida, Y; Horide, T

    SUPERCONDUCTOR SCIENCE & TECHNOLOGY   37 巻 ( 9 )   2024年9月

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    担当区分:最終著者, 責任著者   記述言語:英語   出版者・発行元:Superconductor Science and Technology  

    YBa2Cu3O7 coated conductors are a strategic material for superconducting applications such as high field magnets, fusion, and motors. Grain boundaries reduce the critical current density (Jc) even at a tilt angle as low as 5°, but the successful development of the highly oriented substrates seemed to overcome the weak link problem at grain boundaries. However, it reappears when we visit the homogeneity of the coated conductors. To suppress the weak link in the coated conductors, the Ca doping was investigated. The Ca-doped YBa2Cu3O7 films were fabricated on the moderately oriented substrates. While the grain boundaries in the moderately oriented substrates significantly degraded the Jc without Ca doping, the Ca doping improved the Jc especially at low temperature. This indicates that the tilt angle dependence of Jc was varied by the Ca doping. While the Jc for the moderately oriented substrate was 20 times smaller than that for the highly oriented substrate, the Ca doping restored 1/2 of the Jc for the highly oriented substrate at 40 K and 9 T. The vortex structure changed from Abrikosov Josephson vortices to the Abrikosov vortices with increasing the Ca content. The combination of Ca doping and moderate substrate texture is another design of coated conductors. The Ca doping can patch the local degradation of the substrate texture to mass produce the practical coated conductors with improved homogeneity.

    DOI: 10.1088/1361-6668/ad68d7

    Web of Science

    Scopus

  8. Fabrication of YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7</sub> Superconducting Nanocomposite Film on Silicon Substrate 査読有り

    Bertrand, A; Voulhoux, M; Kuroki, M; Ishimaru, M; Horide, T

    ACS APPLIED ELECTRONIC MATERIALS   6 巻 ( 6 ) 頁: 4601 - 4607   2024年6月

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    担当区分:最終著者, 責任著者   記述言語:英語   出版者・発行元:ACS Applied Electronic Materials  

    Fabrication of YBa2Cu3O7 nanocomposite films on silicon substrates is required for superconducting electromagnetic devices. Low-temperature deposition is effective in suppressing the chemical reaction between YBa2Cu3O7 and Si, while sufficient diffusion is required to form the well-defined nanocomposite structure. The fabrication of the YBa2Cu3O7 nanocomposite films on Si substrates should simultaneously satisfy these conflicting requirements. A YSZ (yttrium stabilized zirconia) buffer layer was epitaxially grown on Si substrates to suppress the chemical reaction. Then, the YBa2Cu3O7 + Ba2YbNbO6 films were fabricated on the YSZ/Si. The nanorods with diameters of 9-17 nm were elongated along the c-axis even at the low deposition temperature. The YBa2Cu3O7 + Ba2YbNbO6 nanocomposite film exhibited a critical temperature of 86.0 K, which is comparable to the critical temperature of 85.6 K in the pure film. The irreversibility temperature was slightly improved by the nanorods. Thus, we demonstrate the formation of nanorods in the YBa2Cu3O7 films on Si substrates without lowering the critical temperature. This opens the superconducting electromagnetic devices integrated with high-temperature superconductors and semiconductors.

    DOI: 10.1021/acsaelm.4c00612

    Web of Science

    Scopus

  9. Evaluation of temperature dependent vortex pinning properties in strongly pinned YBa 2 Cu 3 O 7- d thin fi lms with Y 2 BaCuO 5 nanoinclusions 招待有り

    Jha, AK; Matsumoto, K; Horide, T; Saini, S; Ichinose, A; Mele, P; Yoshida, Y; Awaji, S

    SUPERCONDUCTIVITY   9 巻   2024年3月

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    出版者・発行元:Superconductivity  

    The pinning of quantized magnetic vortices in superconducting YBa2Cu3O7- δ(YBCO or Y123) thin films with Y2BaCuO5 (Y211) nanoinclusions have been investigated over wide temperature range (4.2–77 K). The concentration of Y211 nanoinclusions has been systematically varied inside YBCO thin films prepared by laser ablation technique using surface modified target approach. Large pinning force density values (Fp ∼ 0.5 TNm−3 at 4.2 K, 9 T) have been observed for the YBCO film with moderate concentration of Y211 nanoinclusions (3.6 area % on ablation target). In addition, uniform enhancement in critical current density (Jc) was observed in the angular dependent Jc measurement of YBCO+Y211 nanocomposite films. Y211 nanoinclusions have been found to be very efficient in pinning the quantized vortices thereby enhancing the in-field Jc values over a wide range of temperature. Increasing the concentration of Y211 secondary phase into Y123 film matrix results into agglomeration of Y211 phase and observed as increased Y211 nanoparticle size. These larger secondary phase nanoparticles are not as efficient pinning centers at lower temperatures as they are at higher temperatures due to substantial reduction of the coherence length at lower temperatures. Investigation of the temperature dependence of Jc for YBCO+Y211 nanocomposite films has been conducted and possible vortex pinning mechanism in these nanocomposite films has been discussed.

    DOI: 10.1016/j.supcon.2024.100087

    Web of Science

    Scopus

  10. Metastable Substitution of an Isovalent Anion Element in SnSe Films to Control the Thermoelectric Property 査読有り

    Yamaguchi, K; Ishimaru, M; Horide, T

    ACS APPLIED ELECTRONIC MATERIALS   6 巻 ( 2 ) 頁: 1071 - 1077   2024年1月

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    担当区分:最終著者, 責任著者   出版者・発行元:ACS Applied Electronic Materials  

    To improve the thermoelectric properties of SnSe films, carrier control is required, but elemental doping is difficult due to the thermodynamic solubility limit. Isovalent elements may generate holes or electrons not in a direct manner but in the manner to form point defects. In this study, the Sn(Se,Te) films were fabricated by a pulsed laser deposition (PLD) method to control the carrier concentration by substituting isovalent Te for Se. The coexistence of the orthorhombic and cubic phases at the tens of nanometer scale in the SnSe0.5Te0.5 film was clarified by the structural observation, which is consistent with the equilibrium phase diagram. In spite of the phase coexistence, the lattice parameters linearly increased with an increase in the Te content in the Sn(Se,Te) films. This demonstrates the metastable composition situation for each phase, namely, the carrier control beyond the thermodynamic limit due to the nonequilibrium growth in PLD. As a result, the Seebeck coefficient decreased, and the electrical conductivity increased to increase the power factor, especially in a low temperature near room temperature. The Te substitution in the nonequilibrium PLD increases the hole concentration beyond the thermodynamic solubility limit and thus is effective in controlling the carrier in the SnSe films where carrier doping is difficult.

    DOI: 10.1021/acsaelm.3c01490

    Web of Science

    Scopus

  11. Carrier Control of Bi-Doped SnSe Films for Fabrication of π-Type Thermoelectric Film Modules 査読有り

    Horide, T; Nakamura, K; Ishimaru, M

    ACS APPLIED ENERGY MATERIALS   7 巻 ( 1 ) 頁: 346 - 352   2023年12月

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    担当区分:筆頭著者, 責任著者   掲載種別:研究論文(学術雑誌)   出版者・発行元:ACS Applied Energy Materials  

    Thermoelectric energy conversion is promising for high-efficiency power generation. The p- and n-type thermoelectric materials are required to fabricate high-performance thermoelectric modules. SnSe is one of the highest-performance thermoelectric materials, and SnSe films should be fabricated for small-scale applications. While the p-type SnSe films can be easily prepared without precise control of the doping, it is difficult to control the electron concentration in the n-type SnSe films. In this study, the Bi-doped SnSe films were fabricated at low deposition temperatures by using the self-buffer layer, namely, the SnSe-based buffer layers. The low-temperature deposition on the buffer layer increased the concentration of doped Bi, although the contribution of the buffer layer to the electronic conduction was observed. The π-type thermoelectric module consisting of p-type SnSe and n-type SnSe/buffer layers was fabricated. The output power of 0.09 μW and the open-circuit voltage of 0.11 V were obtained at 155 °C at the cold end and 255 °C at the hot end. The feasibility of fabricating the π-type SnSe film module was demonstrated. By optimizing the buffer layer thickness and increasing the number of legs, we expect the module performance to be further improved.

    DOI: 10.1021/acsaem.3c02683

    Web of Science

    Scopus

  12. Solution deposition planarization of stainless steel foil for fabricating Al-doped ZnO film 査読有り

    Hiraoka, K; Matsumoto, K; Horide, T

    JAPANESE JOURNAL OF APPLIED PHYSICS   62 巻 ( 10 )   2023年10月

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    担当区分:最終著者, 責任著者  

    DOI: 10.35848/1347-4065/ad009f

    Web of Science

  13. Modulation of vortex pinning by matrix defects in YBa2Cu3O7 nanocomposite film 査読有り

    Tomoya Horide, Kento Higashi, Manabu Ishimaru, Tatsunori Okada, Satoshi Awaji and Kaname Matsumoto

    Superconductor Science and Technology   36 巻 ( 10 ) 頁: 105005   2023年8月

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1088/1361-6668/acecad

  14. Nano- to microscale structural and compositional heterogeneity of artificial pinning centers in pulsed-laser-deposited YBa2Cu3O7-y thin films 査読有り

    Kuroki, M; Horide, T; Matsumoto, K; Ishimaru, M

    JOURNAL OF APPLIED PHYSICS   134 巻 ( 4 )   2023年7月

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  15. Observation of anion-stoichiometry phase separation in Fe(Te,Se) film 査読有り

    Horide Tomoya, Ichinose Ataru, Tanaka Masashi, Matsumoto Kaname

    JOURNAL OF APPLIED PHYSICS   133 巻 ( 20 )   2023年5月

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    担当区分:筆頭著者, 責任著者  

    DOI: 10.1063/5.0153801

    Web of Science

  16. Angular Dependence of Magnetizations in a YBa2Cu3O7−x Film with BaHfO3 Nanorods at Low Magnetic Fields 査読有り

    Hiroyuki Deguchi*, Ryota Miake, Hikaru Kawaguchi, Masaki Mito, Tomoya Horide, and Kaname Matsumoto

    JPS Conference Proceedings   38 巻   頁: 011044   2023年

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    記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

    DOI: 10.7566/JPSCP.38.011044

  17. Aligned Self-Organization Induced by Epitaxial Stress and Shear Deformation in Jahn-Teller Spinel ZnMnGaO4 査読有り

    Horide, T ; Morishita, K ; Horibe, Y ; Usuki, M ; Ishimaru, M; Matsumoto, K

    JOURNAL OF PHYSICAL CHEMISTRY C   126 巻 ( 1 ) 頁: 806 - 814   2022年

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1021/acs.jpcc.1c09324

  18. Thermoelectric Property of SnSe Films on Glass Substrate: Influence of Columnar Grain Boundary on Carrier Scattering 査読有り

    Horide, T ; Murakami, Y ; Ishimaru, M ; Matsumoto, K

    ACS APPLIED ELECTRONIC MATERIALS   4 巻 ( 12 ) 頁: 6364 - 6372   2022年

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    担当区分:筆頭著者, 責任著者   掲載種別:研究論文(学術雑誌)  

  19. Self-Organized Nanocomposite Structure Controlled by Elemental Site Occupancy to Improve Vortex Pinning in YBa2Cu3O7 Superconducting Films 査読有り

    Horide, T ; Yoshida, Y ; Kita, R ; Gondo, M ; Ishimaru, M ; Matsumoto, K

    ACS APPLIED ELECTRONIC MATERIALS   4 巻 ( 6 ) 頁: 3018 - 3026   2022年

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    担当区分:筆頭著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)  

    DOI: 10.1021/acsaelm.2c00438

  20. Fabrication of Fe(Te,Se) films added with oxide or chalcogenide: Influence of added material on phase formation and superconducting properties 査読有り

    Horide, T; Katagiri, H ; Ichinose, A; Matsumoto, K

    JOURNAL OF APPLIED PHYSICS   131 巻 ( 10 ) 頁: 103901   2022年

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    担当区分:筆頭著者, 責任著者   記述言語:英語  

▼全件表示

科研費 2

  1. 自己組織化膜の歩留まり科学に向けた計測体系構築:反射電子線小角散乱

    研究課題/研究課題番号:24K21687  2024年6月 - 2027年3月

    科学研究費助成事業  挑戦的研究(萌芽)

    堀出 朋哉, 堀部 陽一

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    担当区分:研究代表者 

    配分額:6500000円 ( 直接経費:5000000円 、 間接経費:1500000円 )

    工業材料は大量生産され、歩留まりを考慮して製品管理や設計を行う必要がある。歩留まりの科学化により、より効率的な大量生産、工業製品使用が可能になる。歩留まり科学では個々のデータの分解能よりもビッグデータ性が重要である。限定詳細評価から高速全箇所評価にかじを切ることが、歩留まり科学への計測思想の転換である。今回は自己組織化薄膜材料をターゲットとする。小角散乱に着目し、In-situで自己組織化構造をデータ化することを可能にする計測体系の構築を目指す。

  2. 磁束運動パーコレーションを用いた計算デバイスの基本原理確立

    研究課題/研究課題番号:22K18812  2022年6月 - 2025年3月

    科学研究費助成事業  挑戦的研究(萌芽)

    堀出 朋哉, 大輪 拓也, 田中 将嗣

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    担当区分:研究代表者 

    配分額:6370000円 ( 直接経費:4900000円 、 間接経費:1470000円 )

    ネットワークの広がりはパーコレーション問題として知られている。本研究ではパーコレーションを扱う新しい計算プラットホームとしてパーコレーション物理コンピュータを生み出すことを目指す。超伝導体に電流を流した時の電圧発生パーコレーションに着目する。局所的に超伝導現象を変調した際の電圧挙動を観察することにより、入力パターン変化によるパーコレーションパス変化を実証する。さらに一般的問題とデバイスのインターフェースとなる数理モデルを構築し、デバイス原理の指針を示す。
    YBa2Cu3O7(YBCO)膜をデバイス応用するにはSi基板上に成膜する必要がある。そこでSi基板上にYBCO膜を成膜した。YBCO膜がエピタキシャルに成長し、臨界温度も85K級とすることに成功した。ナノコンポジット構造を形成することも可能であることも示した。さらに粒界のために臨界電流密度が小さくなっておいることもわかった。臨界電流密度が入力に対する応答のしやすさの指標であり、粒界やナノコンポジット構造により臨界電流密度を調整できることが分かった。YBCO膜において温度や磁場を変化させて抵抗を測定した。磁場を増加、または温度を上げることにより、抵抗が大きくなることを確認した。さらにひずみを用いた入力の可能性も調べた。YBCO膜ではひずみ応答が小さいが、(La,Sr)2CuO4ではひずみ応答が大きく、曲げひずみによる5K級のTc変化を観察した。このように温度、磁場、ひずみをデバイスの入力パラメータとすることができる。
    またデバイス特性を評価する中で、YBCO膜においてパーコレーションが均一性に影響を受けることがわかってきた。YBCO膜には不均一性があり、デバイスの応答に影響を及ぼす可能性がある。電子顕微鏡やX線を用いて不均一性を解析することに着手した。
    さらに相転移パーコレーションを用いた計算という観点からYBCO膜の抵抗評価を行った。不均一な電流分布に対して抵抗の場所依存性を多端子により測定することで磁束相関を評価した。低温になるほど磁束が強い相関を示して運動する。相関のつながり方がパーコレーションすることになり、パーコレーションデバイスの原理になる可能性があることを示した。また本デバイスではレーザーエッチングによるデバイス加工を行っており、フォトリソマスクを作製せずに様々なパターンの加工を施す技術を構築することにも成功した。
    研究代表者が異動したため装置の移設が必要となった。試料作製や評価については環境を構築することと並行して進めた。一方、実験結果の解析に遅れが生じたため、数理モデルとのすり合わせにおいて遅れが生じている。
    電流パス型のパーコレーションデバイスと相転移型のパーコレーションデバイスを提案し、試料作製及び特性評価を行ってきた。パーコレーションデバイスとしての可能性を示す結果は得られている。数理モデルで記述してデバイス化するには、実験結果と数理モデルのすり合わせが必要である。それぞれのデバイスにおいて詳細な特性挙動を評価し、パーコレーションの数理モデルとの対応を明らかにする。