| 研究課題/領域番号 |
19F19353
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| 研究種目 |
特別研究員奨励費
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| 配分区分 | 補助金 |
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| 応募区分 | 外国 |
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| 審査区分 |
小区分28020:ナノ構造物理関連
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| 研究機関 | 東京大学 |
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研究代表者 |
野村 政宏 東京大学, 先端科学技術研究センター, 准教授 (10466857)
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| 研究分担者 |
GUO YANGYU 東京大学, 先端科学技術研究センター, 外国人特別研究員
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| 研究期間 (年度) |
2019-11-08 – 2022-03-31
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| 研究課題ステータス |
完了 (2021年度)
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| 配分額 *注記 |
1,600千円 (直接経費: 1,600千円)
2021年度: 400千円 (直接経費: 400千円)
2020年度: 800千円 (直接経費: 800千円)
2019年度: 400千円 (直接経費: 400千円)
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| キーワード | phonon / phonon hydrodynamics / quantum heat transport / phonon NEGF formalism / recursive algorithm / phonon vortex / Anharmonic phonon NEGF / Fourier’s representation / MPI parallelization / heat transport |
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| 研究開始時の研究の概要 |
We plan to establish the non-equilibrium Green function computational framework with anharmonic phonon-phonon scattering taken into account. Heat transport through silicon and germanium thin films as well as Si/Ge interface will be considered in establishing the algorithm. As a first step, we plan to adopt the modified valence force field empirical atomic interaction models for both silicon and germanium. This computational framework will be validated for heat transport through bulk Si and Ge at different temperatures, and heat transport through Si/Ge interface at room temperature.
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| 研究実績の概要 |
The research achievements under the support of JSPS fellowship mainly include three aspects:
(1) We develop the three-dimensional anharmonic phonon non-equilibrium Green’s function formalism, and a parallelized computational framework for large-scale quantum heat transport simulation. With the new methodology, the open question of how anharmonic phonon-phonon scattering plays the role in heat transport at solid-solid interface is studied with a local spectral energy exchange decomposition scheme. Also we present a novel path to demonstrate phonon localization in graded superlattices and a thermal conductivity minimum phenomenon in the quantum coherent regime.
(2) We develop a mesoscopic simulation framework based on the phonon Boltzmann equation under Callaway’s dual relaxation model with fully ab initio input of phonon properties for both isotropic and anisotropic material systems. With the new method, we investigate the size effect of phonon hydrodynamics in graphitic nano- and micro-structures, and promote the experimental observation of phonon Poiseuille flow in micro-meter-scale isotopically purified graphite ribbon.
(3) We develop a coupled model for heat transport along polar dielectric nanostructures via phonons and surface phonon polaritons. A universal quantum of two-dimensional heat transport in ultrathin polar films is derived for surface phonon polaritons. The non-linear temperature profile due to the coupled dynamics is also demonstrated.
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| 現在までの達成度 (段落) |
令和3年度が最終年度であるため、記入しない。
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| 今後の研究の推進方策 |
令和3年度が最終年度であるため、記入しない。
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