Search results
Results from the WOW.Com Content Network
In physics, polaritons / p ə ˈ l ær ɪ t ɒ n z, p oʊ-/ [1] are bosonic quasiparticles resulting from strong coupling of electromagnetic waves (photon) with an electric or magnetic dipole-carrying excitation (state) of solid or liquid matter (such as a phonon, plasmon, or an exciton).
A quasiparticle emerging from the coupling between a plasmon and a hole: plasmon, hole Plasmon: A coherent excitation of a plasma: electron Plexciton: Coupling plasmons with excitons Polaron: A moving charged quasiparticle that is surrounded by ions in a material electron, phonon Polariton: A mixture of photon with other quasiparticles photon ...
A polaron is a quasiparticle used in condensed matter physics to understand the interactions between electrons and atoms in a solid material. The polaron concept was proposed by Lev Landau in 1933 [1] and Solomon Pekar in 1946 [2] to describe an electron moving in a dielectric crystal where the atoms displace from their equilibrium positions to effectively screen the charge of an electron ...
The coupling of the phonon and the photon is the most promininent in the region where the original transverse disperion relations would have crossed. In the limit of large k , the solid lines of both branches approach the dotted lines, meaning, the coupling does not have a large impact on the behaviour of the vibrations.
A magnon is a quasiparticle, a collective excitation of the spin structure of an electron in a crystal lattice. In the equivalent wave picture of quantum mechanics, a magnon can be viewed as a quantized spin wave. Magnons carry a fixed amount of energy and lattice momentum, and are spin-1, indicating they obey boson behavior.
The A field is the photon, which corresponds classically to the well-known electromagnetic four-potential – i.e. the electric and magnetic fields. The Z field actually contributes in every process the photon does, but due to its large mass, the contribution is usually negligible.
This means that the coupling becomes large at low energies, and one can no longer rely on perturbation theory. Hence, the actual value of the coupling constant is only defined at a given energy scale. In QCD, the Z boson mass scale is typically chosen, providing a value of the strong coupling constant of α s (M Z 2) = 0.1179 ± 0.0010. [7]
Fig 2: Measured photon structure function versus x for Q 2 = 4.3 GeV 2 (blue crosses) and 39.7 GeV 2 (black crosses) compared to the QCD prediction (red, green) explained in the text. The hadronic system produced in two-photon reactions has in general a rather high momentum along the beam direction resulting in small hadronic scattering angles.