Nanoresonators are sensitive devices driven magnetomotively enabling the measurement of interactions with the surrounding media, such as with turbulence and quantized vortices in superfluid ⁴He. Nanoresonators can be assembled using different procedures, including by separation of wire filaments from a segment drawn through a series of dies or by nanofabrication techniques, either as a standing goalpost nanobeam [1] or, as part of this work is currently focused on, through the fabrication of beams directly into the walls of a channel to allow for measurements in driven flows.

The hysteretic behavior of oscillating microwires in superfluid 4He has been reported in earlier studies [2,3]. These experiments generally reveal a threshold at which the slope of the force–velocity curve drops sharply as turbulence develops, either through the development of classical vorticity in the normal fluid component or through the formation of quantized vortices in the superfluid. In the present work, a superconducting NbTi nanowire with a diameter of 560 nm was used to generate and probe turbulence by sweeping the driving force amplitude at various temperatures. At the lowest temperature investigated, approximately 1.4 K, an additional intermediate turbulent state was observed, potentially indicating intriguing physical effects such as distinct vortex configurations or vortex densities resulting in different levels of dissipation. Investigation of this phenomenon is ongoing, and future improvements in the reproducibility and scalability of these devices may enable a more complete interpretation of the underlying mechanisms.

Aside from the measurement of vortex nucleation and vortex-device interaction, these resonators have been developed with the aim of studying local dissipation in non-homogeneous flows such as shear layers or spherically[4]/cylindrically[5] symmetrical thermal counterflow. Moreover, the embedding of multiple nanoresonators in the same channel is also of considerable interest, as it may allow the trapping of vortices between the devices and the excitation of Kelvin wave resonances. Such work could offer new insight into vortex-related dissipation mechanisms and finally provide experimental data on the elusive Kelvin wave cascade [6].

[1] Kamppinen, T., Eltsov, V.B. Nanomechanical Resonators for Cryogenic Research. J Low Temp Phys 196, 283–292 (2019)

[2] D.I. Bradley, A.M. Guénault, S.N. Fisher, R.P. Haley, M.J. Jackson, D. Nye, K. O’Shea, G.R. Pickett, V. Tsepelin, History Dependence of Turbulence Generated by a Vibrating Wire in Superfluid 4He at 1.5 K J Low Temp Phys (2011) 162: 375–382

[3] H. Yano, A. Handa, H. Nakagawa, M. Nakagawa, K. Obara, O. Ishikawa, T. Hata,
Observation of the turbulent flow in superfluid 4He using a vibrating wire,
Journal of Physics and Chemistry of Solids, Volume 66, Issues 8–9, 2005, Pages 1501-1505, ISSN 0022-3697

[4] Dunca, Tomáš & Novotný, Filip & Talí?, Marek & Szalai, Balázs & Ustinov, Nikita & Skrbek, L. & Varga, Emil. (2025). Spherically symmetric counterflow turbulence in open geometry. 10.48550/arXiv.2509.14103. 

[5] Rickinson, E. & Sergeev, Y. & Baggaley, Andrew. (2020). Superfluid turbulence driven by cylindrically symmetric thermal counterflow. Physical Review B. 101. 10.1103/PhysRevB.101.134519. 

[6] Eltsov, V. B. & Lvov, V. S. Amplitude of Waves in the Kelvin-Wave Cascade. Jetp Lett. 111, 389391 (2020)

Keywords
superfluid helium|quantized vortex|nanoresonator|multistability|dissipation