4,199 research outputs found
Current oscillations in a metallic ring threaded by a time-dependent magnetic flux
We study a mesoscopic metallic ring threaded by a magnetic flux which varies
linearly in time PhiM(t)=Phi t with a formalism based in Baym-Kadanoff-Keldysh
non-equilibrium Green functions. We propose a method to calculate the Green
functions in real space and we consider an experimental setup to investigate
the dynamics of the ring by recourse to a transport experiment. This consists
in a single lead connecting the ring to a particle reservoir. We show that
different dynamical regimes are attained depending on the ratio hbar Phi/Phi0
W, being Phi0=h c/e and W, the bandwidth of the ring. For moderate lengths of
the ring, a stationary regime is achieved for hbar Phi/Phi0 >W. In the opposite
case with hbar Phi/Phi0 < W, the effect of Bloch oscillations driven by the
induced electric field manifests itself in the transport properties of the
system. In particular, we show that in this time-dependent regime a tunneling
current oscillating in time with a period tau=2piPhi0/Phi can be measured in
the lead. We also analyze the resistive effect introduced by inelastic
scattering due to the coupling to the external reservoir.Comment: 17 pages, 13 figure
Plasmonic nanoparticle monomers and dimers: From nano-antennas to chiral metamaterials
We review the basic physics behind light interaction with plasmonic
nanoparticles. The theoretical foundations of light scattering on one metallic
particle (a plasmonic monomer) and two interacting particles (a plasmonic
dimer) are systematically investigated. Expressions for effective particle
susceptibility (polarizability) are derived, and applications of these results
to plasmonic nanoantennas are outlined. In the long-wavelength limit, the
effective macroscopic parameters of an array of plasmonic dimers are
calculated. These parameters are attributable to an effective medium
corresponding to a dilute arrangement of nanoparticles, i.e., a metamaterial
where plasmonic monomers or dimers have the function of "meta-atoms". It is
shown that planar dimers consisting of rod-like particles generally possess
elliptical dichroism and function as atoms for planar chiral metamaterials. The
fabricational simplicity of the proposed rod-dimer geometry can be used in the
design of more cost-effective chiral metamaterials in the optical domain.Comment: submitted to Appl. Phys.
Unknown classical electrodynamics
In this paper, we analyze some little-known inconsistencies and inaccuracies in classical electrodynamics and suggest ways to eliminate them
Decomposing the dynamics of heterogeneous delayed networks with applications to connected vehicle systems
Delay-coupled networks are investigated with nonidentical delay times and the
effects of such heterogeneity on the emergent dynamics of complex systems are
characterized. A simple decomposition method is presented that decouples the
dynamics of the network into node-size modal equations in the vicinity of
equilibria. The resulting independent components contain distributed delays
that map the spatiotemporal complexity of the system to the time domain. We
demonstrate that this new approach can be used to reveal new physical phenomena
in heterogenous vehicular traffic when vehicles are linked via
vehicle-to-vehicle (V2V) communication.Comment: The paper has been updated in response to referee comments. 5 pages,
2 figure
- …