arXiv subjects

Jayme De Luca

Publications and source records attributed to Jayme De Luca.

23 records · Page 2Linked to original sources

arXiv2001

Perfectly Translating Lattices on a Cylinder

We perform molecular dynamics simulations on an interacting electron gas confined to a cylindrical surface and subject to a radial magnetic field and the field of the positive background. In order to study the system at lowest energy states that still carry a current, initial configurations are obtained by a special quenching procedure. We observe the formation of a steady state in which the entire electron-lattice cycles with a common uniform velocity. Certain runs show an intermediate instability leading to lattice rearrangements. A Hall resistance can be defined and depends linearly on the magnetic field with an anomalous coefficient reflecting the manybody contributions peculiar to two dimensions.

cond-mat.stat-mech↗

arXiv2000

Direct-interaction electrodynamics of a two-electron atom

We study numerically the dynamical system of a two-electron atom with the Darwin interaction as a model to investigate scale-dependent effects of the relativistic action-at-a-distance electrodynamics. This dynamical system consists of a small perturbation of the Coulomb dynamics for energies in the atomic range. The key properties of the Coulomb dynamics are: (i) a peculiar mixed-type phase space with sparse families of stable non-ionizing orbits and (ii) scale-invariance symmetry, with all orbits defined by an arbitrary scale parameter. The combination of this peculiar chaotic dynamics ((i) and (ii)), with the scale-dependent relativistic corrections (Darwin interaction) generates the phenomenon of scale-dependent stability: We find numerical evidence that stable non-ionizing orbits can exist only for a discrete set of resonant energies. The Fourier transform of these non-ionizing orbits is a set of sharp frequencies. The energies and sharp frequencies of the non-ionizing orbits we study are in the quantum atomic range.

nlin.CD↗

arXiv1999

Long Range Magnetic Order and the Darwin Lagrangian

We simulate a finite system of $N$ confined electrons with inclusion of the Darwin magnetic interaction in two- and three-dimensions. The lowest energy states are located using the steepest descent quenching adapted for velocity dependent potentials. Below a critical density the ground state is a static Wigner lattice. For supercritical density the ground state has a non-zero kinetic energy. The critical density decreases with $N$ for exponential confinement but not for harmonic confinement. The lowest energy state also depends on the confinement and dimension: an antiferromagnetic cluster forms for harmonic confinement in two dimensions.

cond-mat.stat-mech↗

arXiv1998

Electrodynamics of a two-electron atom with retardation and self-interaction effects

We study the linear stability of a circular orbit in a two-electron atom, with the inclusion of retardation and self-interaction effects. We calculate all the eigenvalues of the linear stability of the circular orbit, expanded up to third order in (v/c). We discuss how the linear stability results can be used to construct a resonant normal form constant of motion, which is important for the short time stability of the orbits (e.g. emission of sharp spectral lines). We calculate the magnitudes related to some of those orbits and compare to the quantum atomic results.

chao-dyn↗

arXiv1997

Electrodynamics of helium with retardation and diffusion along the center manifold of Wannier orbits

We show that an extra complex constant of motion with an analytic form can exist in the neighborhood of some discrete Wannier orbits of helium, when one includes retardation and self-interaction effects. The energies of these discrete Wannier orbits are in the correct atomic magnitude. The highest frequency in the stable manifold of one such orbit agrees with the highest frequency sharp line (2P-1S) of parahelium to within two percent. The generic term of the frequency in the stable manifold to higher orbits is also in agreement with the asymptotic form of quantum mechanics for helium.

chao-dyn↗