Experimental study on dynamic superfluid response of 4He confined in 1D nano-channel

2017 Fiscal Year Final Research Report

• Project/Area Number: 26400352
• 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: The University of Electro-Communications
• Principal Investigator: Taniguchi Junko 電気通信大学, 大学院情報理工学研究科, 助教 (70377018)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 低次元系 / 超流動 / 朝永‐ラッティンジャー液体

Outline of Final Research Achievements

In the system of one-dimensional (1D) 4He, a dynamical superfluid response is expected to appear. Our purpose is to clarify how the superfluid specific to 1D becomes prominent. First, we studied the channel diameter dependence of superfluid response. When the channel diameter is reduced from 2.8 to 2.5 nm, the superfluid grows gradually with decreasing temperature, differently from the rather rapid rise for 2.8 nm. In the narrower channel, thermal activation of phase slip occurs at the lower temperature, which breaks the superfluid coherence at the lower temperature than the onset of dynamical one.
We also studied the dilute limit that the dynamical superfluid response appears for 2.8 nm channel. We found that under the unsaturated vapor pressure, a dilute liquid exists in the channel and shows a dynamical superfluid response with a large frequency dependence. We succeeded in explaining the superfluid response from dilute to pressurized liquid by the TL liquid model.

Free Research Field

低温物理