Related papers: Optical forces from near-field directionalities in…
We calculate optical forces and torques exerted on a chiral dipole by chiral light fields and reveal genuinely chiral forces in combining the chiral contents of both light field and dipolar matter. Here, the optical chirality is…
Up to now, in the literature of optical manipulation, optical force due to chirality usually coexists with the non-chiral force and the chiral force usually takes a very small portion of the total force. In this work, we investigate a case…
A two-dimensional periodic optical force field, which combines conservative dipolar forces with vortices from radiation pressure, is proposed in order to influence the diffusion properties of optically susceptible nano-particles. The…
We put forward a theory on the optical force exerted upon a dipolar particle by a stationary and ergodic partially coherent light field. We show through a rigorous analysis that the ensemble averaged electromagnetic force is given in terms…
By using a method, previously established to calculate electromagnetic fields, we compute the force of light upon a metallic particle. This procedure is based on both Maxwell's Stress Tensor and the Couple Dipole Method. With these tools,…
Using a two-dipole model of an optical near-field of Scanning Near-field Optical Microscope tip, i. e. taking into account contributions of magnetic and electric dipoles, we propose and analyze a new type of 3D optical nanotrap found for…
Optical forces are often calculated by discretizing the trapping light beam into a set of rays and using geometrical optics to compute the exchange of momentum. However, the number of rays sets a trade-off between calculation speed and…
The center-of-mass motion of optically trapped dielectric nanoparticles in vacuum is extremely well-decoupled from its environment, making a powerful tool for measurements of feeble sub-attonewton forces. We demonstrate a method to trap and…
Optical trapping, where microscopic particles are trapped and manipulated by light is a powerful and widespread technique, with the single-beam gradient trap (also known as optical tweezers) in use for a large number of biological and other…
It is shown that a circular dipole can deflect the focused laser beam that induces it, and will experience a corresponding transverse force. Quantitative expressions are derived for Gaussian and angular tophat beams, while the effects…
Optical pulling forces or tractor beams can pull particles against light propagation by redirecting the incident photons forward. This is typically achieved using Bessel beams with very small half-cone angles, which considerably limits its…
Forces on a nanoparticle in an optical trap are analysed. Brownian motion is found to be one of the major challenges to trap a nanoparticle. Accordingly, suitable spatial electric field distribution of laser beam is suggested to enhance the…
Structural chirality can induce counter-intuitive optical forces due to inherent symmetry properties. While optical forces on a single chiral particle in the Rayleigh regime have been well studied, optical forces in coupled chiral particles…
Nanoscale forces play an important role in different scanning probe microscopies, most notably atomic force microscopy (AFM). In contrast, in scanning near-field optical microscopy (SNOM) a light-induced coupled local optical polarization…
A photon carries a momentum of, so one may anticipate light to "push" on any object standing in its path via the scattering force. In the absence of intensity gradient, using a light beam to pull a particle backwards is counter intuitive.…
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…
We demonstrate both theoretically and experimentally that gradients in the phase of a light field exert forces on illuminated objects, including forces transverse to the direction of propagation. This effect generalizes the notion of the…
Optical trapping is a widely used technique, with many important applications in biology and metrology. Complete modelling of trapping requires calculation of optical forces, primarily a scattering problem, and non-optical forces. The…
Near-field patterns of light provide a way to optically trap, deliver and sort single nanoscopic particles in a wide variety of applications in nanophotonics, microbiology and nanotechnology. Using rigorous electromagnetic theory, we…
Collective coherent light scattering by polarizable particles creates surprisingly strong, long range inter-particle forces originating from interference of the light scattered by different particles. While for monochromatic laser beams…