Optimal Cooling of Multiple Levitated Particles through Far-Field Wavefront-Shaping

TL;DR

This paper introduces a novel method using time-dependent scattering matrices to simultaneously cool multiple levitated particles with complex shapes by shaping the wavefronts of light in real-time.

Contribution

It presents a new formalism that leverages scattering matrix information to engineer adaptive light fields for multi-particle cooling.

Findings

Proposes a robust formalism for multi-particle cooling.

Suggests an experimental approach using stroboscopic scattering measurements.

Enables simultaneous cooling of particles with arbitrary shapes.

Abstract

Light forces can be harnessed to levitate mesoscopic objects and cool them down towards their motional quantum ground state. Significant roadblocks on the way to scale up levitation from a single to multiple particles in close proximity are the requirements to constantly monitor the particles' positions as well as to engineer complex light fields that react fast and appropriately to their movements. Here, we present an approach that solves both problems at once. By exploiting the information stored in a time-dependent scattering matrix, we introduce a robust formalism enabling the identification of spatially modulated wavefronts, which simultaneously cool down multiple levitated objects of arbitrary shapes. An experimental implementation is suggested based on stroboscopic scattering-matrix measurements and time-adaptive injections of modulated light fields.