Optical traps use forces exerted by specially structured beams of light to localize microscopic objects in threedimensions. In the case of single-beam optical traps, such as optical tweezers, trapping is due entirely to gradientsin the light's intensity. Gradients in the light field's phase also...
Negative nonconservative forces: optical “tractor beams” for arbitrary objects. Phys. Rev. Lett. 107, 203602 (2011). Article ADS CAS PubMed Google Scholar Roichman, Y., Sun, B., Roichman, Y., Amato-Grill, J. & Grier, D. G. Optical forces arising from phase gradients. Phys. Rev...
With optical forces arising from phase gradients, it is crucial to also have sharp axial gradients if optical axial confinement is required and it is undesirable to resort to other forces for axial confinement (e.g., gravity force or normal force from sample chamber). On the other hand, beam...
We show how the phase-gradient force can be designed to efficiently change the speed of the nanoparticles. We have found that multiple hot nanoparticles assemble in the form of a quasi-stable group whose motion around the laser trap is also controlled by such optical propulsion forces. This ...
Grier, Optical forces arising from phase gradients. Phys. Rev. Lett. 100, 013602 (2008) Article ADS Google Scholar A. Mazolli, P.A. Maia Neto, H.M. Nussenzveig, Theory of trapping forces in optical tweezers. Proc. Royal Soc. London A. 459, 30213041 (2003) Article MathSciNet ...
(S*) is given at the proper time, mirror image vortices begin to rotate around crossings of critical contours of transverse gradients of phase and stimulus intensity. On the basis of this theory, a vulnerable domain was described. Its timing occurred just before complete recovery from previous ...
This can be associated with the molecular forces, binding the molecules together and restricting their mobility. Since the phonon modes manifesting in the THz spectra mainly originate from external, lattice vibrations, they are very sensitive to crystal packing and so the intermolecular interactions, ...
From the image, very fine parallel layer-like growth pattern is seen which reveals smoothness of the surface. The intrinsic structure of organic molecules forces them to stack in layers and intermolecular forces like hydrogen and van der Waals bond can generate layered growth during crystal growth ...
The balance between these two forces produces an equilibrium point near the focus. Optical tweezers, based on field gradients, rely on changing this equilibrium point to manipulate trapped bodies in three dimensions. Optical tweezers have multiple applications in biological and physical sciences. In ...
The optical microscope has revolutionized biology since at least the 17th Century. Since then, it has progressed from a largely observational tool to a powerful bioanalytical platform. However, realizing its full potential to study live specimens is hind