Fundamental Study of Vortex State using Mono-layer superfluid Heliumu Films formed in Porous Media

使用多孔介质中形成的单层超流 Heliumu 膜进行涡旋态的基础研究

• 批准号: 14340100
• 负责人: KUBOTA Minoru
• 金额: $ 9.54万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14340100/
• 关键词: 2 D superfluid; 3D superfluid; Quantized vortices; 3D vortex excitation

We have studied 3D superfluid made from an ideal 2D system, a superfluid made of ^4He mono-atomic-layer film formed on a solid surface. We know such a system undergoes a typical 2D superfluid transtion, KT transition if the surface is fiat. When the ^4He mono-atomic-layer is formed on a surface which is interconnected 3D wise, we may expect a 3D phase transition. We have made an extensive experimental study utilizing very sensitive torsional oscillators to study this superfluidity and vortices in such 3D connected ^4He mono-atomic-layer films. We have used our unique rotating cryostat for experiments under rotation. The followings are the major results:1].3D vortices core size has been derived from the detailed study of 3D superfluid density in the absolute unit, namely (kg/m^3) using the Josephson's relation. The result is compared with the 2D vortex core size of 25 □ and actually 3D core is always a few times larger than the pore diameter of the substrate.2].Vortex lines threading through the substrate are expected to be produced in the 3D superfluid. Our recent result shows the first clear experimental evidence of 3D vortices created under steady rotation. An energy dissipation peak originates from 2D vortices in a KT films near transition temperature. The 3D system made of He films condensed on 3D connected surface now produce 3D vortices and the superfluid velocity field induced by the 3D vortices induce extra energy dissipation.3].Superfiow through the 3D superfluid made of ^4He mono-atomic-layer film is further a good tool to study this unique system. Newly introduced continuously operable refrigerator now is ready for such kind of experiments using superflow.

我们研究了由理想的二维系统构成的三维超流体，理想的二维系统是由^4He单原子层在固体表面形成的超流体。我们知道这样的系统经历了一个典型的二维超流相变，如果表面是平坦的，KT相变。当^4He单原子层形成在三维互连的表面上时，我们可以预期三维相变。我们利用非常灵敏的扭转振子对这种三维连通^4He单原子层薄膜中的超流和涡旋进行了广泛的实验研究。我们使用我们独特的旋转低温恒温器进行旋转实验。主要结果如下：1）通过对三维超流密度绝对单位（kg/m^3）的详细研究，利用Josephson关系式导出了三维涡核尺寸。结果与25 □的2D涡核尺寸进行了比较，实际上3D涡核总是比基底的孔径大几倍。[2].在3D超流体中有望产生穿过基底的涡线。我们最近的结果显示了稳定旋转下产生的三维涡流的第一个明确的实验证据。在相变温度附近，KT薄膜中的能量耗散峰源于二维涡旋。由He膜凝聚在三维连通表面上形成的三维系统产生了三维涡旋，由三维涡旋诱导的超流速度场引起了额外的能量耗散。[3]通过由^4He单原子层膜构成的三维超流的超流是研究这一独特系统的一个很好的工具。新推出的连续运行制冷机已经为这类超流实验做好了准备。

项目成果

Minoru Kubota, Toshiaki Obata, Ryousuke Ishiguro, Minoru Yamashita, Takeshi Igarashi, Emi Hayata, Osamu Ishikawa, Yutaka Sasaki, Nikolay Mikhin, Muneyuki Fukuda, Vladimir Kovacik, Takao Mizusaki: "Super uldity and quantized vortex studies under rotation u

Minoru Kubota、Toshiaki Obata、Ryousuke Ishiguro、Minoru Yamashita、Takeshi Igarashi、Emi Hayata、Osamu Ishikawa、Yutaka Sasaki、Nikolay Mikhin、Muneyuki Fukuda、Vladimir Kovacik、Takao Mizusaki：“旋转 u 下的超强度和量子化涡旋研究

M.Fukuda^1, M.K.Zalalutdmov^1, V.Kovacik^1, T.Minoguchi^2, T.Obata^1, M.Kubota^1, E.B.Sonin: "Rotation-induced 3D vorticity in 4He superfluid films adsorbed on a porous glass"arXiv : cond-mat/0405092 v2 10. (2004)

M.Fukuda^1、M.K.Zalalutdmov^1、V.Kovacik^1、T.Minoguchi^2、T.Obata^1、M.Kubota^1、E.B.Sonin：“吸附在 4He 超流体薄膜中的旋转引起的 3D 涡度

Emiko Ishikawa, Ryo Shoda, Nahoko Matsuura, Masanori Ono, Toyoaki Eguchi, Akira Sakai, Minoru Kubota, Yukio Hasegawa: "Development of ultralow temperature scanning tunneling microscope cooled by a dilution refrigerator"e-J. Surf. Sci. Nanotech.. Vol.2. 15

Emiko Ishikawa、Ryo Shoda、Nahoko Matsuura、Masanori Ono、Toyoaki Eguchi、Akira Sakai、Minoru Kubota、Yukio Hasekawa：“通过稀释冰箱冷却的超低温扫描隧道显微镜的开发”e-J。

M.Yamashita, A.Matsubara, R.Ishiguro, Y.Sasaki, 0.Ishikawa, M.Kubota, Y.M.Bunkov, T.Mizusaki: "Rotating Liquid 3He in Aerogel"Journal of Low Temperature Physics. Vol.134. 749-155 (2004)

M.Yamashita、A.Matsubara、R.Ishiguro、Y.Sasaki、0.Ishikawa、M.Kubota、Y.M.Bunkov、T.Mizusaki：“气凝胶中旋转液体 3He”低温物理学杂志。

H.Araki, M.Nakamura, S.Harada, T.Obata, N.Mikhin, V.Syvokon, M.Kubota: "Phase Diagram of Hydrogen in Palladium"Journal of Low Temperature Physics. 134. 1145-1151 (2004)

H.Araki、M.Nakamura、S.Harada、T.Obata、N.Mikhin、V.Syvokon、M.Kubota：“钯中氢的相图”低温物理学杂志。