Superfluid nanomechanical resonator for quantum nanofluidics

TL;DR

This paper introduces a superfluid nanomechanical resonator that detects quantum flow in nanofluidic channels, enabling studies of superfluid properties and turbulence at the nanoscale.

Contribution

It presents a novel nanomechanical device integrating superfluid helium with nanofluidic channels for sensitive quantum flow detection and thermodynamic analysis.

Findings

Measured superfluid fraction at various pressures.

Observed onset of quantum turbulence in confined geometry.

Developed a model for superfluid nanomechanical dynamics.

Abstract

We have developed a nanomechanical resonator, for which the motional degree of freedom is a superfluid 4He oscillating flow confined to precisely defined nanofluidic channels. It is composed of an in-cavity capacitor measuring the dielectric constant, which is coupled to a superfluid Helmholtz resonance within nanoscale channels, and it enables sensitive detection of nanofluidic quantum flow. We present a model to interpret the dynamics of our superfluid nanomechanical resonator, and we show how it can be used for probing confined geometry effects on thermodynamic functions. We report isobaric measurements of the superfluid fraction in liquid 4He at various pressures, and the onset of quantum turbulence in restricted geometry.