Related papers: Enhanced optical trapping via structured scatterin…
Super-oscillating beams can be used to create light spots whose size is below the diffraction limit with a side ring of high intensity adjacent to them. Optical traps made of the super-oscillating part of such beams exhibit superior…
It was theoretically proposed and experimentally demonstrated that anti-reflection coating allows one to trap a high dielectric sphere, at the same time enhancing the transverse optical force. Here, by explicitly calculating the gradient…
A nanofiber-based optical tweezer is demonstrated. Trapping is achieved by combining attractive near-field optical gradient forces with repulsive electrostatic forces. Silica-coated Fe$_2$O$_3$ nanospheres of 300 diameter are trapped as…
We experimentally demonstrate stable trapping and controlled manipulation of silica microspheres in a structured optical beam consisting of a dark focus surrounded by light in all directions - the so-called Dark Focus Tweezer. Results from…
Optically-levitated nanoparticles in vacuum offer a pristine platform for high-quality mechanical oscillators, enabling a wide range of precision measurements and quantum technologies. A key performance metric in such systems is the…
Optical trapping has proven to be a valuable experimental technique for precisely controlling small dielectric objects. However, due to their very nature, conventional optical traps are diffraction limited and require high intensities to…
We demonstrate photophoretic force-based optical trapping of multiple absorbing particles in air by loosely focusing a Gaussian beam with a series of convex lenses of different focal lengths, and investigate the dependence of the number of…
The dynamics of an optically trapped particle are often determined by measuring intensity shifts of the back-scattered light from the particle using position sensitive detectors. We present a technique which measures the phase of the…
While conventional optical trapping techniques can trap objects with submicron dimensions, the underlying limits imposed by the diffraction of light generally restrict their use to larger or higher refractive index particles. As the index…
The superposition of a Gaussian mode and a Laguerre-Gauss mode with $\ell=0,p\neq0$ generates the so-called bottle beam: a dark focus surrounded by a bright region. In this paper, we theoretically explore the use of bottle beams as an…
Micron sized, neutral, non-dielectric particles immersed in a viscous fluid can be trapped in the focal plane of a Gaussian beam. A particle can absorb energy from such a beam with a large radial intensity gradient, resulting in substantial…
An extended interference pattern close to surface may result in both a transmissive or evanescent surface fields for large area manipulation of trapped particles. The affinity of differing particle sizes to a moving standing wave light…
Optical trapping describes the interaction between light and matter to manipulate micro-objects through momentum transfer. In the case of 3D trapping with a single beam, this is termed optical tweezers. Optical tweezers are a powerful and…
Optical tweezers enable non-contact trapping of micro-scale objects using light. Despite their widespread use, it is currently not known how tightly it is possible to three-dimensionally trap micro-particles with a given photon budget.…
Orbital optical trapping of a dielectric micro-particle in air was studied experimentally using a lensed, counter-propagating dual-beam trap, and by numerical simulations employing ray optics. The essential attributes of particle dynamics…
Optical binding interactions between laser-trapped spherical microparticles are familiar in a wide range of trapping configurations. Recently it has been demonstrated that these experiments can be accurately modeled using Mie scattering or…
The successful development and optimisation of optically-driven micromachines will be greatly enhanced by the ability to computationally model the optical forces and torques applied to such devices. In principle, this can be done by…
We present an optical nanotrapping setup that exhibits enhanced efficiency, based on localized plasmonic fields around sharp metallic features. The substrates consist of laser-structured silicon wafers with quasi-ordered microspikes on the…
Photophoretic forces - which are of thermal origin - have defined an alternative route of optical trapping of absorbing microparticles in air. Here, we show that a single multi-mode fiber facilitates significantly more robust optical traps…
Focused laser beams allow controlling mechanical motion of objects and can serve as a tool for assembling complex micro and nano structures in space. While in a vast majority of cases small particles experience attractive gradient forces…