1) All-optical sub-Kelvin sympathetic cooling of a levitated microsphere in vacuum

Date Published: August 24, 2022

Ewan Wright's work on the paper "All-optical sub-Kelvin sympathetic cooling of a levitated microsphere in vacuum," published by Optica, with research partners Yoshi Arita, Gordon Bruce, Steve Simpson, Pavel Zemánek, and Kishan Dholakia has garnered media attention from Phys.org and Mirage News

According to the paper's abstract, "We demonstrate all-optical sympathetic cooling of a laser-trapped microsphere to sub-Kelvin temperatures, mediated by optical binding to a feedback-cooled adjacent particle. Our study opens prospects for multi-particle quantum entanglement and sensing in levitated optomechanics...We show, for the first time, the use of this optical binding to perform sympathetic cooling: by applying PFB cooling to one particle, the adjacent particle is sympathetically cooled to sub-Kelvin temperatures."

This publication opens up exciting possibilities for exploring why the quantum effects that govern the behavior of atoms and molecules are not seen on an everyday scale and could lead to future research into quantum entanglement with large objects.

Read the Paper


Wright research graphs

Fig. 2. (a) Experimental observations of power spectral density of the sympathetically cooled particle at different gas pressures. These temperatures are measured while the PFB cooled particle is at 𝑇=105K, 9.8K, 1.1K, and 0.4K for each gas pressure. (b) Sympathetic cooling of a microsphere (red asterisks) via optical binding to the particle that is PFB cooled (blue crosses). The dashed line is a baseline curve for a single, rotating microsphere in the absence of PFB cooling. Inset: two trapped vaterite microspheres, where the scale bar shows 5µm.