A model is proposed to calculate the melting points of nanoparticles based on Lennard-Jones (L-J) potential function. The effects size, shape, and atomic volume surface packing are considered in model. model, L-J function for spherical nanoparticles, agrees with experimental values gold (Au) lead (Pb) nanoparticles. function, consistent Qi Wang's that predicts Gibbs-Thompson relation. Moreover, non-integer can be used predict Tm

The classical dynamics of a cold atom trapped inside vertical rotating helical optical tube (HOT) is investigated by taking also into account the gravitational field. resulting equations motion are solved numerically. rotation HOT induces for an initially at rest. result action two inertial forces, namely, centrifugal force and Coriolis force. Both forces to rotate in direction opposite that angular velocity HOT. frequency turning points atom's global oscillation can be controlled value...

The classical dynamics of a cold atom trapped inside static helical optical potential is investigated based on the Lagrangian formalism, which takes into account both light field and gravitational field. resulting equations motion are solved numerically analytically. topology potential, drives atom, responsible for two different types oscillations, namely: local whereby atomic confined in region smaller than wavelength global when extended to larger regions comparable beam Rayleigh range...

We determine how a system composed of two nonidentical two-level atoms with different resonance frequencies and damping rates could work as nanoantenna for controlled mode switching light routing. calculate the angular distribution emitted field detected in far-field zone including direct interatomic interactions arbitrary linear dimensions system. The calculation is carried out terms symmetric antisymmetric modes two-atom find that long are identical, emission cannot be switched between...

We study the directional properties of a radiation field emitted by geometrically small system composed two identical two-level emitters located at short distances and driven an optical vortex beam, Laguerre-Gaussian beam which possesses structured phase amplitude. find that may operate as nanoantenna for controlled tunable emission. Polar diagrams intensity are presented showing constant or amplitude difference positions plays essential role in directivity patterns differ dramatically...

The impact of nanoparticles size on the cohesive energy was investigated by Morse potential for different metallic cubic structures. decreases with reducing its size, which is agree corresponding experimental values Mo and W nanoparticle. It found that if parameter α increases then range interatomic decreases.

A new generalized Morse potential function with an additional parameter m is proposed to calculate the cohesive energy of nanoparticles. The calculations showed that a using different values for and α parameters can be used predict experimental Moreover, enlargement attractive force in plays important role describing stability nanoparticles rather than softening repulsive interaction cases when > 1.

In this paper a model for the calculation of major and minor hysteresis loops in particulate systems is described. For case system with aligned easy axes, based on numerical solution rate equation which was modified to take into account particle size distribution interaction effects. addition, calculations orientation axes have been made. model, effects are represented using mean field approach, i.e. Hi Mwhere Mis average magnetization system. The results show that non-interacting case, no...

The classical dynamics of a cold atom trapped inside vertical rotating helical optical tube (HOT) is investigated by taking also into account the gravitational field. resulting equations motion are solved numerically. rotation induces for an initially at rest. result action two inertial forces, namely centrifugal force and Coriolis force. Both forces to rotate in direction opposite that angular velocity HOT. frequency turning points atom's global oscillation can be controlled value However,...

In a recent experiment Shegai <i>et al.</i>¹ have shown that bimetallic particle dimer composed of gold and silver atoms may work as directional frequency filter which scatters light different frequencies in directions. A phase difference between emitters required for the scattering was determined by complex polarizabilities therefore varies with size, shape material composition particles accordance their plasmon resonance characteristics. this paper, we give theoretical...

We propose the construction of an atom mirror for cold three-level atoms in a dark state where forces, responsible atomic reflection, are provided by artificial gauge fields. These fields created from total internal reflection optical vortex beams with Gaussian intensity profiles at interface dielectric prism and vacuum. investigate role photon angular momentum magnitude these consequently on efficiency reflection.