Related papers: Optical alignment and spinning of laser-trapped mi…
A linearly polarized Gaussian beam, carrying zero net spin angular momentum, is conventionally not expected to exert optical torque or induce rotational motion in birefringent microparticles. When such a beam is tightly focused, the…
Optical vortex beams carry orbital angular momentum and thus exert torque on illuminated objects. A dielectric microtool - a microbarbell - is used in a two-laser optical tweezers to measure the torque of a focused optical vortex. The tool…
Optical tweezers have become a powerful tool for measuring parameters of microscale and nanoscale local environments. Motion of particles within optical tweezer traps established itself as a probe for local viscosity, temperature as well as…
The spin transfer torque is a phenomenon in which angular momentum of a spin polarized electrical current entering a ferromagnet is transferred to the magnetization. The effect has opened a new research field of electrically driven…
We demonstrate experimentally an optical process in which the spin angular momentum carried by a circularly polarized light beam is converted into orbital angular momentum, leading to the generation of helical modes with a wavefront…
We provide a vivid demonstration of the mechanical effect of transverse spin momentum in an optical beam in free space. This component of the Poynting momentum was previously thought to be virtual, and unmeasurable. Here, its effect is…
In this work, we optically trapping microparticles with higher order Frozen Wave using holographic optical tweezers. Frozen Waves are diffraction resistant optical beams, obtained by superposing copropagating Bessel beams with the same…
Spin-orbit interactions in optics traditionally describe an influence of the polarization degree of freedom of light on its spatial properties. The most prominent example is the generation of a spin-dependent optical vortex upon focusing or…
A circularly polarized rotationally symmetric paraxial laser beams carries hbar angular momentum per photon as spin. Focussing the beam with a rotationally symmetric lens cannot change this angular momentum flux, yet the focussed beam must…
Manipulating mega biomolecules and micro-devices with light is highly appealing. Opto driving torque can propel micro-rotors to translational motion in viscous liquid, and then separate microsystems according to their handedness. We study…
We report on the observation and measurement of the transfer of transverse angular momentum to birefringent particles several wavelengths in size. A trapped birefringent particle is much larger than the nano-particles systems for which…
In light beams with circular or elliptic polarization, the transverse energy flow consists of the "spin" and "orbital" parts. Both of them can induce the orbital motion of microparticles suspended within the field of a light beam, and this…
Photons carry one unit of angular momentum associated with their spin~\cite{Beth1936}. Structured vortex beams carry additional orbital angular momentum which can also be transferred to matter~\cite{Allen1992}. This extra twist has been…
Optical beams with a new and distinctive type of helicity have become the subject of much recent interest. While circularly polarised light comprises photons with spin angular momentum, these optically engineered 'twisted beams' (optical…
Optical vortex beams are a type of topological light characterized by their inherent orbital angular momentum, leading to the propagation of a spiral-shaped wavefront. In this study, we focus on two-dimensional electrons with Rashba and…
Non-invasive optical manipulation of particles has emerged as a powerful and versatile tool for biological study and nanotechnology. In particular, trapping and rotation of cells, cell nuclei and sub-micron particles enables unique…
We have developed a scheme to measure the optical torque, exerted by a laser beam on a phase object, by measuring the orbital angular momentum of the transmitted beam. The experiment is a macroscopic simulation of a situation in optical…
Custom-designed colloidal particles in an optical tweezers act as light-mills in a fluid. In particular, aqueous suspensions of capped colloids, in which half of the surface is covered with metal layers, are investigated. Due to their…
Optically-induced mechanical torque leading to the rotation of small objects requires the presence of absorption or breaking cylindrical symmetry of a scatterer. A spherical non-absorbing particle cannot rotate due to the conservation of…
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…