Development of a novel method for measuring thermal conductivity of small solids using thermal mode spectroscopy

• Project/Area Number: 16K13719
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: General applied physics
• Research Institution: Osaka University
• Principal Investigator: Ogi Hirotsugu 大阪大学, 大学院工学研究科, 教授 (90252626)
• Co-Investigator(Kenkyū-buntansha): 中村 暢伴 大阪大学, 基礎工学研究科, 助教 (50452404) ; 石田 秀士 大阪大学, 基礎工学研究科, 助教 (80283737)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000); Fiscal Year 2017: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000); Fiscal Year 2016: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 熱モード / 熱伝導率 / 固有値問題 / レーザー計測 / 共振 / 固有値 / 固有ベクトル / 物性実験 / 超精密計測 / 物性理論

Outline of Final Research Achievements

Heat conduction possesses (thermal) modes in analogy with acoustics even without oscillation. Here, we establish thermal-mode spectroscopy to measure thermal diffusivity of small specimens. Local heating with a light pulse excites such modes that show antinodes at the heating point, and photothermal detection at another antinode spot allows measuring relaxation behavior of the desired mode selectively: The relaxation time yields thermal diffusivity. The Ritz method is proposed for arbitrary geometry specimens. This method is applicable even to a diamond crystal with mm dimensions.

Research Products

• [Journal Article] Thermal mode spectroscopy for thermal diffuusivity of millimeter-size solids (2016)
  • Author(s): H. Ogi, T. Ishihara, H. Ishida, A. Nagakubo, N. Nakamura, and M. Hirao
  • Journal Title: Physical Review Letters Volume: 117 Issue: 19 Pages: 195901-195901
  • DOI: 10.1103/physrevlett.117.195901
  • Peer Reviewed
• [Presentation] 熱モードスペクトロスコピーによる熱拡散係数測定に関する数値的検証 (2017)
  • Author(s): 石田秀士、荻博次、金里征治、河原源太
  • Organizer: 日本物理学会第72回年次大会
• [Presentation] 熱モードスペクトロスコピー：熱の共振という概念 (2017)
  • Author(s): 荻 博次
  • Organizer: 日本非破壊検査協会 平成29年度第2回「超音波による非接触材料評価研究会」
  • Invited
• [Presentation] 固体の熱モードの選択的励起 (2016)
  • Author(s): 荻博次, 石田秀士, 石原達也, 平尾雅彦
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 金沢大学（石川県金沢市）
  • Year and Date: 2016-09-15