Quantum properties of Bose and Fermi fluids in one-dimensional states

我们研究了氦吸附在具有从纳米笼到三维连通孔的规则结构的新型纳米孔中。通过吸附蒸汽压观察被吸附氦的吸附势和层的形成。在纳米笼和纳米通道中分别实现了零维和一维氦流体的新范式。超流体在一维和三维纳米孔中的发生（转变）与孔隙连接有明显的相关性。三维孔隙中的超流体具有类似于三维玻色原子气体的玻色-爱因斯坦凝聚的性质。在4He预涂纳米孔中形成的3He气体薄膜表现出随孔连接的维度交叉：随着温度的降低，从二维玻尔兹曼气体到一维或三维气体状态。在较低的温度下，3he气体在每个维度上都变成简并态。对平面基底上的4He薄膜进行了超高频超流测量，确定了4He薄膜的超流涡参数。

We have studied helium adsorbed in new nanopores which have regular structures from nano-cage to three-dimensionally (3D) connected pores. Adsorption potential and layer formation of the adsorbed helium are observed by the vapor pressure for the adsorption. New paradigms of zero-D and 1D helium fluids are realized in nano-cages and nano-channels, respectively. The superfluid onsets (transitions) in the 1D and 3D nanopores show obvious dependence on the pore connections. The superfluid in the 3D pores has properties similar to the Bose-Einstein condensation of the 3D Bose atomic gas. The films of the 3He gas formed in the 4He preplated nanopores show the dimensional crossover depending on the pore connection : from the 2D Boltzmann gas to a 1D or 3D gas state with decreasing temperature. This 3He-gas changes to the degenerate state in each dimension at the lower temperatures. Extremely high frequency superfluid measurements of 4He films on flat substrate determined the superfluid vortex parameters of the 4He films.