All-electrical cooling of an optically levitated nanoparticle

The cooling of levitated nanoparticles is a major step in optomechanics, aiming at both fundamental physics experiments and sensing applications, but using nonlinear cooling schemes and electro-optic modulation devices can significantly elevate the cost and complexity of the experiment. The authors implement a practical all-electrical controller capable of cooling the center-of-mass motion of a levitated nanoparticle to sub-Kelvin temperatures. When combined with improved vacuum and detection, this method can provide a simple and direct platform for three-dimensional near-ground-state cooling of the nanoparticle's motional state.