Low-dimensional quantum fluids, where one can probe the effects of enhanced thermal and quantum fluctuations on macroscopic quantum wave functions, can be experimentally realized through transverse physical confinement of superfluid helium on scales smaller than the coherence length. Reaching this scale is difficult, requiring confinement in single or multiple pores with nanometer radii. Porous silicates such as MCM-41 have a pore radius larger than the coherence length of ${}^4\mathrm{He}$, and in this work we systematically explore the possibility of preplating pores with different elements to reduce the pore size without localizing the confined superfluid. Through a direct solution of the few-body Schrödinger equation combined with quantum Monte Carlo simulations, we explore the behavior of helium confined inside cylindrical nanopores for a range of preplating elements, including rare gases and alkali metals. For rare gases, we find that helium remains strongly attracted to the pore walls and any atoms in the core form an incompressible liquid. For alkali metals such as Cs, weak interactions between helium and the preplating material prevent localization near the walls and enable delocalization in the pore center. Our results extend previous results for helium wetting on flat two-dimensional coated substrates to the curved geometry inside nanopores, and demonstrate that alkali-metal preplated nanopores may enable a tunable one-dimensional confined quantum liquid of helium.

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• Wetting
• 1-dimensional systems
• Helium-4 superfluids
• Porous materials
• Path-integral Monte Carlo