38 citations · 117 across the 11 of their papers we have counts for
11 papers
Tailoring radiation pressure on infinite slab using pair of non-collinear plane waves
R. Ali, R. S. Dutra, S. Iqbal
The electromagnetic field exerts radiation pressure on the matter and tends to move it either in the backward or forward direction due to net optical pulling or pushing force, resp…
Enantioselective optical forces in gain-functionalized single core-shell chiral nanoparticles
R. Ali, F. A. Pinheiro, R. S. Dutra +2
We propose a gain-assisted enantioselective scheme in dye-doped chiral particles, demonstrating optical pulling and pushing forces that can be tuned using externally controllable p…
Probing the screening of the Casimir interaction with optical tweezers
L. B. Pires, D. S. Ether, B. Spreng +13
We measure the colloidal interaction between two silica microspheres in aqueous solution in the distance range from m to m with the help of optical tweezers. When e…
Enantioselection and chiral sorting of single microspheres using optical pulling forces
R. Ali, R. S. Dutra, F. A. Pinheiro +1
We put forward a novel, twofold scheme that enables at the same time all-optical enantioselection and sorting of single multipolar chiral microspheres based on optical pulling forc…
Theory of optical tweezing of dielectric microspheres in chiral host media and its applications
Rfaqat Ali, R. S. Dutra, F. A. Pinheiro +2
We report for the first time the theory of optical tweezers of spherical dielectric particles embedded in a chiral medium. We develop a partial-wave (Mie) expansion to calculate th…
Tailoring optical pulling forces with composite microspheres
R. Ali, F. A. Pinheiro, R. S. Dutra +1
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…
Probing the optical chiral response of single nanoparticles with optical tweezers
R. Ali, F. A. Pinheiro, R. S. Dutra +2
We propose an enantioselective scheme to sort homogeneous chiral particles using optical tweezers. For a certain range of material parameters, we show that a highly focused circula…
Enantioselective manipulation of chiral nanoparticles using optical tweezers
R. Ali, F. A. Pinheiro, F. S. S. Rosa +2
We put forward an enantioselective method for chiral nanoparticles using optical tweezers. We demonstrate that the optical trapping force in a typical, realistic optical tweezing s…
Negative optical torque on a microsphere in optical tweezers
K. Diniz, R. S. Dutra, L. B. Pires +3
We show that the optical force field in optical tweezers with elliptically polarized beams has the opposite handedness for a wide range of particle sizes and for the most common co…
Optimizing optical tweezing with directional scattering in composite microspheres
R. Ali, F. A. Pinheiro, F. S. S. Rosa +2
Trapping of microspheres with a single focused laser beam is usually limited to materials with relative refractive indexes slightly larger than one. We show that directional light…
Optical tweezers absolute calibration
R S Dutra, N B Viana, P A Maia Neto +1
Optical tweezers are highly versatile laser traps for neutral microparticles, with fundamental applications in physics and in single molecule cell biology. Force measurements are p…