Non-magnetic Replacement and Ballistic Thermal Conductivity in Frastrated Quantum Spin System of 2-dimensional Quantum Solid

• Project/Area Number: 23540401
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Condensed matter physics II
• Research Institution: University of Tsukuba
• Principal Investigator: MORISHITA Masashi 筑波大学, 数理物質系, 助教 (90251032)
• Co-Investigator(Kenkyū-buntansha): TAKAGI Takeo 福井大学, 工学研究科, 教授 (00266723) ; 高木 丈夫 福井大学, 工学(系)研究科(研究院), 教授 (00206723)
• Project Period (FY): 2011-04-28 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥5,070,000 (Direct Cost: ¥3,900,000、Indirect Cost: ¥1,170,000); Fiscal Year 2013: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2012: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2011: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000)
• Keywords: ヘリウム / 薄膜 / グラファイト / 朝永-Luttinger液体 / Dirac粒子 / 低次元系 / 単原子層膜 / 低次元 / ヘリウム薄膜 / 熱容量 / 吸着構造 / domain wall / Dirac粒子系 / ２次元 / 量子固体 / 熱伝導 / 2次元 / 量子スピン / 三角格子 / カゴメ格子 / バリスティック

Outline of Final Research Achievements

The heat capacity of a small amount of He-3 atoms solved in He-4 films adsorbed on graphite surfaces has been measured.The results strongly suggest that helium atoms only exhibit fluidity inside domain walls. This behavior has not been observed in any other system and is very unusual. Furthermore, He-3 atoms in domain walls are expected to behave as Tomonaga-Luttinger liquid or massless Dirac fermions.

Research Products

• [Journal Article] Heat Capacity of Dilute 3He-4He Films on Graphite (2013)
  • Author(s): Masashi Morishita
  • Journal Title: Journal of Low Temperature Physics Volume: 171 Issue: 5-6 Pages: 664-669
  • DOI: 10.1007/s10909-012-0803-4
  • Peer Reviewed
• [Presentation] グラファイト上ヘリウム薄膜におけるDirac粒子系 (2015)
  • Author(s): 森下将史
  • Organizer: 日本物理学会第70回年次大会
  • Place of Presentation: 早稲田大学（東京）
  • Year and Date: 2015-03-23
• [Presentation] Fluidity of Domain Walls in Dilute 3He-4He Mixture Films (2014)
  • Author(s): Masashi Morishita
  • Organizer: 27th International Conference on Low Temperature Physics (LT27)
  • Place of Presentation: Buenos Aires(Argentina)
  • Year and Date: 2014-08-07
• [Presentation] グラファイト上ヘリウム薄膜におけるDirac粒子系 (2014)
  • Author(s): 森下将史
  • Organizer: 物性研短期研究会「スーパーマターが拓く新量子現象」
  • Place of Presentation: 東京大学物性研究所（千葉県）
  • Year and Date: 2014-04-18
• [Presentation] グラファイト上ヘリウム４薄膜 domain wallの流動性 (2014)
  • Author(s): 森下将史
  • Organizer: 日本物理学会第69回年次大会
  • Place of Presentation: 東海大学(神奈川県)
• [Presentation] Reentrant Solidification of First Layer of 4He Film on Graphite” (2013)
  • Author(s): Masashi Morishita
  • Organizer: International Symposium on Quantum Fluids and Solids (QFS2013)
  • Place of Presentation: Matsue(Japan)
• [Presentation] グラファイト上ヘリウム４薄膜吸着第１原子層の状態 (2013)
  • Author(s): 森下将史
  • Organizer: 日本物理学会2013年秋季大会
  • Place of Presentation: 徳島大学(徳島県)
• [Presentation] Does the 4/7 phase exist in 4He Film Adsorbed on Graphite? (2012)
  • Author(s): Masashi Morishita
  • Organizer: 物性研短期研究会「量子凝縮系におけるdefectsとtopology」
  • Place of Presentation: 東京大学物性研究所（柏市）
• [Presentation] Solidification of Second Atomic Layer of 4He Film Adsorbed on Graphite (2011)
  • Author(s): Masashi Morishita
  • Organizer: 26th International Conference on Low Temperature Physics (LT26)
  • Place of Presentation: Beijing, China
• [Presentation] グラファイト上吸着3He-4He薄膜の固化 (2011)
  • Author(s): 森下将史
  • Organizer: 日本物理学会201１年秋季大会
  • Place of Presentation: 富山大学（富山市）
• [Presentation] Heat Capacity of Dilute 3He-4He Films on Graphite
  • Author(s): Masashi Morishita
  • Organizer: International Symposium on Quantum Fluids and Solids (QFS2012)
  • Place of Presentation: Lancaster University（イギリス）
• [Presentation] グラファイト上ヘリウム４薄膜吸着第２原子層の状態
  • Author(s): 森下将史
  • Organizer: 日本物理学会201１年秋季大会
  • Place of Presentation: 横浜国立大学