Ultrafast viscosity measurement of a trapped particle

In our latest article, Lars Madsen, Catxere CasacioAlex Terrasson, Warwick Bowen and collaborators measure the viscosity of a particle within twenty microseconds and extreme precision—up to the point where the remnant uncertainty stems from its thermal molecular collisions. Read on in Nature Photonics!

A bead trapped in optical tweezers performs thermally driven motion.
From: Madsen, Lars S. et al. Ultrafast viscosity measurement with ballistic optical tweezers. Nat. Photonics (2021)

Making mechanical qubits

Yasmine Sfendla, Chris Baker, Glen Harris, Ray Harrison, Warwick Bowen and collaborating professor Lin Tian from UC Merced have set a step towards developing the elusive all-mechanical qubit. All you need is some superfluid and a slab of silicon! Get the recipe at npj Quantum Information.

Computer-simulated image of a thin film of fluid covering a periodically perforated slab. In the middle, a hole is missing. There, the fluid is moving up and down like water in a pond.
Superfluid wave trapped in a phononic crystal (or “acoustic metamaterial”).
From: Sfendla, Yasmine L., et al. Extreme quantum nonlinearity in superfluid thin-film surface waves. npj Quantum Inf 7, 62 (2021)