Entangled Photons (original) (raw)

Plasmon-supported emission of entangled photons and zero-point energy

Emission of pairs of photons in the interface metal-dielectric under the laser excitation arising due to the time-dependent perturbation of the zero-point fluctuations of the electromagnetic field by photons of the laser is considered. The enhancement of this emission by surface plasmons may be used for getting polarization-entangled photons. A possibility to compensate the energy of the zero-point fluctuations of bosons by other fluctuations with negative energy is discussed.

Applications of plasmonics: general discussion

Faraday discussions, 2015

responded: It is a Raman scattering process. The photon interacts with the hybrid (because they are ultrastrongly coupled) qubit-waveguide. Aer the interaction, the photon emitted has less energy. This energy stays in an excited state of the hybrid qubit-waveguide. We have checked this picture in our numerical calculations.

Energy-Time Entanglement Preservation in Plasmon-Assisted Light Transmission

Physical Review Letters, 2005

We report on experimental evidences of the preservation of energy-time entanglement for extraordinary plasmonic light transmission through sub-wavelength metallic hole arrays, and for long range surface plasmon polaritons. Plasmons are shown to coherently exist at two different times separated by much more than the plasmons lifetime. This kind of entanglement involving light and matter is expected to be useful for future processing and storing of quantum information.

PLASMONS AND SINGLE PARTICLE EXCITATIONS IN MODULATION DOPED QUANTUM WELLS

Journal De Physique, 1987

Le mouvement des Clectrons dans les diffkrentes couches d'un systkme de N couches parall&les d'Clectrons est coup16 par les forces Coulombiennes. Ainsi, dans le cas ok kll < l/d, d &ant la distance sCparant les couches et kll le vecteur d'onde parallel au plan dkfini par ces couches, il y a N modes propres des plasmons. La diffgrence d'knergie entre les modes propres des plasmons est une mesure de l'intkraction de Coulomb entre les couches. Nous mesurons la dispersion de ces modes discrets des plasmons B l'aide de la diffusion Rarnan en polarisation parallkle des photons incidents et des photons diffuds. En polarisation croide, nous mesurons les spectres des fluctuations de la densit6 de spin. Dans une approximation simple, ces spectres sont goportionels aux spectres d'excitation des paires Clectron-trous. Nous po6vons bien expliquer ces spectres et leur changement avec la tempkrature par la partie imaginaire de la fonction Lindhard en diux dimension. -Abstract. In a layered electron gas with N layers the Coulomb interaction between layers correlates the motion of electrons on different lavers. Thus for k~i < l/d, where d is the interlaver separation and k the in plane wavevector, the piasmon eigenmdes fan out into N discrete mbdes. With parallel pokrisation of incident and scattered light, we measure the dispersion with kII of the discrete plasmon eigen modes with Raman scattering. In crossed polarisation the electronic Raman spectra are proportional to the 2D spin density fluctuation spectra. In a simple theory these spectra are proportional to the single particle excitation spectra. We find good agreement of the measured spectra and their temperature dependence with the imaginary part of the Lindhard dielectric response function.

Preservation of entanglement and quantum correlations next to periodic plasmonic nanostructures

Quantum Information Processing, 2019

We study quantum correlations dynamics of two identical V-type quantum systems initially prepared in an extended Werner-like state, where each one independently interacts with a plasmonic nanostructure. Each V-type system can be decomposed as a two-level system with an additional third external level acting as an "umbrella level." As the plasmonic nanostructure, we use a two-dimensional array of metalcoated dielectric nanoparticles. For the calculations, we combine quantum dynamics calculations using the density matrix equations and classical electromagnetic calculations. In order to describe the entanglement, we use the measure of entanglement of formation, while we use quantum discord to describe the total quantum correlations of our composite system. We find that the presence of the plasmonic nanostructure leads to high suppression of spontaneous emission rates along with a high degree of quantum interference. These phenomena affect the evolution of both entanglement and quantum discord, while they significantly prolong their dynamics.

Single-plasmon interferences

Science Advances, 2016

Surface plasmon polaritons are electromagnetic waves coupled to collective electron oscillations propagating along metal-dielectric interfaces, exhibiting a bosonic character. Recent experiments involving surface plasmons guided by wires or stripes allowed the reproduction of quantum optics effects, such as antibunching with a single surface plasmon state, coalescence with a two-plasmon state, conservation of squeezing, or entanglement through plasmonic channels. We report the first direct demonstration of the wave-particle duality for a single surface plasmon freely propagating along a planar metal-air interface. We develop a platform that enables two complementary experiments, one revealing the particle behavior of the single-plasmon state through antibunching, and the other one where the interferences prove its wave nature. This result opens up new ways to exploit quantum conversion effects between different bosonic species as shown here with photons and polaritons.

Collective phenomena in photonic, plasmonic and hybrid structures

Optics Express, 2011

Preface to a focus issue of invited articles that review recent progress in studying the fundamental physics of collective phenomena associated with coupling of confined photonic, plasmonic, electronic and phononic states and in exploiting these phenomena to engineer novel devices for light generation, optical sensing, and information processing.