Excimers He2* as Tracers of Quantum Turbulence in 4He in the T=0 Limit

TL;DR

This study investigates how metastable He2* excimer molecules interact with quantized vortices in superfluid helium at near-zero temperature, revealing their potential as tracers for quantum turbulence.

Contribution

It provides quantitative measurements of excimer trapping diameters on vortices and demonstrates their ability to be transported by vortex tangles in superfluid helium.

Findings

Trapping diameter is 96 nm at 0.1 bar pressure.

Trapping diameter is 27 nm at 5.0 bar pressure.

Excimers can be carried by vortex tangles through superfluid helium.

Abstract

We have studied the interaction of metastable $^4$He$_2^*$ excimer molecules with quantized vortices in superfluid $^4$He in the zero temperature limit. The vortices were generated by either rotation or ion injection. The trapping diameter of the molecules on quantized vortices was found to be $96\pm6$\,nm at a pressure of 0.1\,bar and $27\pm5$\,nm at 5.0 bar. We have also demonstrated that a moving tangle of vortices can carry the molecules through the superfluid helium.