Study of helium three Fermi fluids with controlled interaction and dimensionality

相互作用和维数受控的氦三费米流体研究

基本信息

批准号：
14340104
负责人：
WADA Nobuo
金额：
$ 9.47万
依托单位：
Nagoya University
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 2004
项目状态：
已结题

项目摘要

Helium 3 and 4 are typical Fermi and Bose quantum fluids, respectively. In addition to these bulk fluids in three-dimension (3D) and helium films on flat solid surfaces studied so far, we have been studying these quantum fluids confined into nanometer-scale pores that have regular structures from zero to three dimensions. The correlations in these helium fluids can be widely controlled by the density (the amount adsorbed).In the present research, we have established a method to know experimentally how helium atoms form uniform layers on the nanopore walls whose pore diameters are only a few times of the helium atom diameter. In the 1D nano-tunnels of FSM-16,we made helium quantum fluid film tubes on solid helium layers. The 4He Bose fluid tubes show a 1D phonon heat capacities at sufficiently low temperatures where the motion in the crosssection of the tube is in the ground state. We obtained the pore size dependence of the gap energy Δ between the ground state and the first excited state. When a dilute 3He fluid film tubes were formed in the 1D 2.8nm pores preplated by the solid 4He layers, the 3He nanotubes show crossover from the 2D Boltzmann gas at higher temperatures than the gap energy to a 1D degenerate Fermi state at sufficiently low temperatures than Δ/10, below about 30mK.For the 4He fluid films in 3D nanopores of HMM-2 with 2.7nm pore diameter, an obvious evidence of the 3D superfluid transition is suggested by a peak of the heat capacity close to the superfluid onset of the 4He films in contrast to the 2D superfluid transition.In relations to the quantum nuclear magnetic states of the solid 3He, organic antiferromagnets and frustrated magnets have been studied. An S=1 Kagome antiferromagnet with a non-magnetic quantum ground state at zero field was found to have a 1/2 plateau of the magnetization curve.

氦3和4分别是典型的费米和玻色量子烟。除了这些散装液体（3D）和氦膜中的这些散装液体外，到目前为止，固体表面上的氦气膜还迄今还研究了这些量子液体，这些量子液体仅限于纳米尺度孔中，这些孔孔具有从零到三个维度的常规结构。这些氦气中的相关性可以由密度（吸附的量）广泛控制。在当前的研究中，我们建立了一种方法，可以通过实验了解氦原子在纳米孔壁上如何形成孔直径仅几次氦原子原子直径的几次。在FSM-16的1d纳米螺纹螺纹中，我们在固体氦层上制造了氦量子流体膜。 4he bose流体管在足够低的温度下显示1D声子热容量，其中管子的横截面运动处于基态。我们获得了基态和第一个激发态之间间隙能δ的孔径依赖性。当在由固体4He层预先准备的1d 2.8nm孔中形成稀释的3he流体膜管时，3he纳米管在温度更高的温度下从2D玻尔兹曼气体到比1d fermi的温度下的2D Boltzmann气体在高度低的温度下进行了比以下30m的1d fermi fram。 HMM-2的直径为2.7nm，这是3D超氟化过渡的一个明显证据，这是通过接近4HE膜超级流体发作的高峰与2D超氟化物过渡相反。 A = 1 kagome抗铁磁铁在零场处具有非磁性量子基态的磁化曲线1/2平原。