English

Fully suspended nano-beams for quantum fluids

Mesoscale and Nanoscale Physics 2022-04-25 v2

Abstract

Non-invasive probes are keystones of fundamental research. Their size, and maneuverability (in terms of e.g. speed, dissipated power) define their applicability range for a specific use. As such, solid state physics possesses e.g. Atomic Force Microscopy (AFM), Scanning Tunneling Microscopy (STM), or Scanning SQUID Microscopy. In comparison, quantum fluids (superfluid 3^3He, 4^4He) are still lacking probes able to sense them (in a fully controllable manner) down to their smallest relevant lengthscales, namely the coherence length ξ0\xi_0. In this work we report on the fabrication and cryogenic characterization of fully suspended (hanging over an open window, with no substrate underneath) Si3_3N4_4 nano-beams, of width down to 50 nm and quality factor up to 10510^5. As a benchmark experiment we used them to investigate the Knudsen boundary layer of a rarefied gas: 4^4He at very low pressures. The absence of the rarefaction effect due to the nearby chip surface discussed in Gazizulin et al. [1] is attested, while we report on the effect of the probe size itself.

Keywords

Cite

@article{arxiv.2111.05278,
  title  = {Fully suspended nano-beams for quantum fluids},
  author = {Ilya Golokolenov and Baptiste Alperin and Bruno Fernandez and Andrew Fefferman and Eddy Collin},
  journal= {arXiv preprint arXiv:2111.05278},
  year   = {2022}
}
R2 v1 2026-06-24T07:32:39.275Z