The Experts below are selected from a list of 225 Experts worldwide ranked by ideXlab platform

Mu Wang - One of the best experts on this subject based on the ideXlab platform.

  • Tuning the Dispersion Relation of a plasmonic waveguide via graphene contact
    EPL (Europhysics Letters), 2014
    Co-Authors: Yu Zhou, Cheng Wang, Ren-hao Fan, Kun Zhang, Ru-wen Peng, Mu Wang
    Abstract:

    In this work, we have investigated experimentally and theoretically the Dispersion Relation of a plasmonic slab waveguide, where the thin gold film with nano-aperature arrays is sandwiched by graphene and a silica layer on a silicon chip. It is shown that the plasmonic slab waveguides are compatible with silicon technology. We have found that when the light waves irradiate the nanostructured waveguides with or without graphene, surface plasmon polaritons are always excited at the metal-dielectric interface due to the interaction between the surface charge oscillation and the electromagnetic field of the light. But in the slab waveguide with graphene, the resonant dips definitely shift in the reflection spectra, which indicates that the contact of graphene can tune the Dispersion Relation of the waveguide in the visible regime. Experimental measurements on optical reflections are in good agreement with calculated plasmonic band structures. Further calculations show that the Dispersion Relation of plasmonic slab waveguides can be tuned by electron doping and the nonlinear effect of graphene. The investigations provide a way to actively control the Dispersion Relation of plasmonic waveguides on silicon chips and benefit the development graphene-related active optical devices.

Govind P Agrawal - One of the best experts on this subject based on the ideXlab platform.

  • exact Dispersion Relation for nonlinear plasmonic waveguides
    Physical Review B, 2011
    Co-Authors: Ivan D Rukhlenko, Asanka Pannipitiya, Malin Premaratne, Govind P Agrawal
    Abstract:

    We derive an exact Dispersion Relation for the surface plasmon polaritons of a nonlinear plasmonic waveguide using exact field decomposition of TM waves. Our approach generalizes the known linear Dispersion Relations to the case of a medium nonlinearity of the form ${\ensuremath{\varepsilon}}_{\mathit{NL}}={\ensuremath{\varepsilon}}_{L}+\ensuremath{\alpha}{|\mathbf{E}|}^{2n}$. We apply the unique Dispersion Relation to a plasmonic waveguide with a Kerr-type nonlinearity $(n=1)$ and show that it enables backward-propagating modes. It also introduces critical points in the energy spectrum of surface plasmon polaritons that result in enhanced interaction of nonlinear modes with each other and external electromagnetic fields.

Alberto Iglesias - One of the best experts on this subject based on the ideXlab platform.

  • Lorentz symmetric Dispersion Relation from a random Hamiltonian
    Physical Review D, 2015
    Co-Authors: Andreas Albrecht, Alberto Iglesias
    Abstract:

    We match the density of energy eigenstates of a local field theory with that of a random Hamiltonian order by order in a Taylor expansion. In our previous work we assumed Lorentz symmetry of the field theory, which entered through the Dispersion Relation. Here we extend that work to consider a generalized Dispersion Relation and show that the Lorentz symmetric case is preferred, in that the Lorentz symmetric Dispersion Relation gives a better approximation to a random Hamiltonian than the other local Dispersion Relations we considered.

R. M. Gupta - One of the best experts on this subject based on the ideXlab platform.

Xinmin Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Primordial perturbations with a modified Dispersion Relation
    Physical Review D, 2009
    Co-Authors: Yi-fu Cai, Xinmin Zhang
    Abstract:

    In this paper we study the generation of primordial perturbations with a modified Dispersion Relation in various cosmological evolution scenarios. We stress that the formation of the power spectrum is strongly dependent on the background. By parameterizing a modified Dispersion Relation, we have listed all potential conditions on background evolution in order to seed scale-invariant primordial spectra. Working in a bounce model with a matterlike contracting phase, we obtain a red-tilted spectrum due to the modified Dispersion Relation.