Optical levitation using broadband light

Abstract

The ability to create dynamic, tailored optical potentials has become important across fields ranging from biology to quantum science. We demonstrate a method for the creation of arbitrary optical tweezer potentials using the broadband spectral profile of a superluminescent diode combined with the chromatic aberration of a lens. A tunable filter, typically used for ultrafast laser pulse shaping, allows us to manipulate the broad spectral profile and therefore the optical tweezer potentials formed by focusing of this light. We characterize these potentials by measuring the Brownian motion of levitated nanoparticles in vacuum and also demonstrate interferometric detection and feedback cooling of the particle’s motion. This simple and cost-effective technique will enable wide application and allow rapid modulation of the optical potential landscape in excess of megahertz frequencies.