1,445 research outputs found
Single Photon Ignition of Two-photon Super-fluorescence through the Vacuum of Electromagnetic Field
The ignition of two-quantum collective emission of inverted sub-ensemble of
radiators due to mutual interaction of this sub-ensemble with other two dipole
active atomic subsystems in process of two-photon exchanges between the atoms
through the vacuum field is proposed. The three particle resonances between
two-photon and single quantum transitions of inverted radiators from the
ensemble are proposed for acceleration of collective decay rate of bi-photons,
obtained relatively dipole-forbidden transitions of excited atomic
sub-ensemble. This mutual interaction between three super-fluorescent processes
in subatomic ensembles take place relatively dipole-forbidden transitions in
one of radiator subsystem. The collective resonance emission and absorption of
two-quanta have nontraditional behavior, accompanied with acceleration and
inhibition of collective emission processes of photons
Coherence Proprieties of Entangled Bi-Modal Field and Its Application in Holography and Communication
This chapter examines the coherence properties of two modes of entangled photons and its application quantum communication and holography. It is proposed novel two-photon entangled sources which take into account the coherence and collective phenomena between the photon belonging to two different modes obtained in two-photon cooperative emission or Raman or lasing. The generation of the correlated bimodal entangled field in two-photon emission or Raman Pump, Stokes and anti-Stokes modes is proposed in the free space and cavity-induced emission. The application two-photon and Raman bimodal coherent field in communication and holography are given in accordance with the definition of amplitude and phase of such entangled states of light. At first, this method does not appear to be essentially different in comparison with the classical coherent state of information processing, but if we send this information in dispersive media, which separates the anti-Stokes and Stokes photons from coherent entanglement fields, the information is drastically destroyed, due to the quantum distribution of photons in the big number modes may be realized in the situation in which the mean value of strength of bimodal field tends to zero. The possibility of restoration of the signal after the propagation of the bimodal field through different fibers, we may restore the common square amplitude and phase
Cooperative Spontaneous Lasing and Possible Quantum Retardation Effects
The collective decay effects between the dipole-active three-level subsystems in the nonlinear interaction with dipole-forbidden transitions, like
2
S
−
1
S
of hydrogen-like radiators, are proposed, taking into consideration the cooperative exchanges between two species of atoms through the vacuum field in the scattering and the two-photon resonance processes. One of them corresponds to the situation when the total energy of the emitted two photons by the three-level radiator in the cascade configuration enters into the two-photon resonance with another type of dipole-forbidden transitions of hydrogen-like (or helium-like) atoms. The similar situation appears in the cooperative scattering between two species of quantum emitters when the difference of the excited energies of the two dipole-active transitions of the three-level radiators is in the resonance with the dipole-forbidden transitions of the Hydrogen-like radiators. These effects are accompanied by the interference between single- and two-quantum collective transitions of the inverted radiators from the ensemble. The two-particle collective decay rate is defined in the description of the atomic correlation functions taking into consideration the phase retardation between them. The kinetic equations which describe the cooperative processes as the function of time and correlation are obtained. The behavior of the system of radiators at short and long time intervals in comparison with the retardation time between them is studied
Optically and Electrically Tunable Dirac Points and Zitterbewegung in Graphene-Based Photonic Superlattices
We demonstrate that graphene-based photonic superlattices provide a versatile
platform for electrical and all-optical control of photonic beams with
deep-subwavelength accuracy. Specifically, by inserting graphene sheets into
periodic metallo-dielectric structures one can design optical superlattices
that posses photonic Dirac points (DPs) at frequencies at which the spatial
average of the permittivity of the superlattice, ,
vanishes. Similar to the well-known zero- bandgaps, we show that these
zero- DPs are highly robust against structural disorder. We
also show that, by tuning the graphene permittivity via the optical Kerr effect
or electrical doping, one can induce a spectral variation of the DP exceeding
\SI{30}{\nano\meter}, at mid-IR and THz frequencies. The implications of this
wide tunability for the photonic Zitterbewegung effect in a vicinity of the DP
are explored too.Comment: 5 pages, 5 figures, to appear in Phys. Rev. B as a Rapid
Communicatio
Anderson Localization at the Subwavelength Scale and Loss Compensation for Surface-Plasmon Polaritons in Disordered Arrays of Metallic Nanowires
Using a random array of coupled metallic nanowires as a generic example of
disordered plasmonic systems, we demonstrate that the structural disorder
induces localization of light in these nanostructures at a deep-subwavelength
scale. The ab initio analysis is based on solving the complete set of 3D
Maxwell equations. We find that random variations of the radius of coupled
plasmonic nanowires are sufficient to induce the Anderson localization (AL) of
surface-plasmon polaritons (SPPs), the size of these trapped modes being
significantly smaller than the wavelength. Remarkably, the optical-gain
coefficient, needed to compensate losses in the plasmonic components of the
system, is much smaller than the loss coefficient of the metal, which is
obviously beneficial for the realization of the AL in plasmonic nanostructures.
The dynamics of excitation and propagation of the Anderson-localized SPPs are
addressed too.Comment: 5 pages, 4 figures, to appear in Phys. Rev.
Ultrafilter and Constructible topologies on spaces of valuation domains
Let be a field and let be a subring of . We consider properties
and applications of a compact, Hausdorff topology called the "ultrafilter
topology" defined on the space Zar of all valuation domains having
as quotient field and containing . We show that the ultrafilter topology
coincides with the constructible topology on the abstract Riemann-Zariski
surface Zar. We extend results regarding distinguished spectral
topologies on spaces of valuation domains.Comment: Comm. Algebra (accepted for publication
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