# Coherent vortex dynamics in a strongly-interacting superfluid on a silicon chip

## TL;DR

This paper presents a novel on-chip platform for observing coherent vortex dynamics in a strongly-interacting superfluid helium droplet, enabling new studies of quantum turbulence and potential quantum technologies.

## Contribution

It introduces an on-chip method to directly observe and control vortex dynamics in a 2D superfluid, overcoming surface effects that hinder such studies.

## Key findings

- Coherent vortex dynamics observed with suppressed thermal diffusion
- On-chip platform enables nondestructive, single-shot vortex decay observation
- Potential applications in astrophysics and quantum sensing

## Abstract

Two-dimensional superfluidity and quantum turbulence are directly connected to the microscopic dynamics of quantized vortices. However, surface effects have prevented direct observations of coherent vortex dynamics in strongly-interacting two-dimensional systems. Here, we overcome this challenge by confining a two-dimensional droplet of superfluid helium at microscale on the atomically-smooth surface of a silicon chip. An on-chip optical microcavity allows laser-initiation of vortex clusters and nondestructive observation of their decay in a single shot. Coherent dynamics dominate, with thermal vortex diffusion suppressed by six orders-of-magnitude. This establishes a new on-chip platform to study emergent phenomena in strongly-interacting superfluids, test astrophysical dynamics such as those in the superfluid core of neutron stars in the laboratory, and construct quantum technologies such as precision inertial sensors.