Liquid Time Crystals

TL;DR

This paper introduces an instrument to study gravitationally bouncing fluid droplets, enabling the creation and observation of long-lived classical time crystals, which serve as a platform to compare quantum and classical non-equilibrium phenomena.

Contribution

The authors developed a novel experimental setup with a droplet printer to generate and analyze long-lived classical time crystals under periodic driving.

Findings

Created and observed time crystals for over 100,000 oscillations

Demonstrated controlled deposition of droplets on fluid surface

Provided data for comparing quantum and classical time crystal behaviors

Abstract

We have constructed and characterised an instrument to study gravitationally bouncing droplets of fluid, subjected to periodic driving force. Our system incorporates a droplet printer that enables an on-demand computer controlled deposition of droplets on the fluid surface. We demonstrate the operation of this instrument by creating and observing long-lived and interacting time crystals whose evolution we have witnessed for more than one hundred thousand oscillation periods. Our observations provide points of comparison for experiments that differentiate between quantum and classical time crystal behaviours in driven non-equilibrium systems.