6 research outputs found
Momentum of an electromagnetic wave in dielectric media
Almost a hundred years ago, two different expressions were proposed for the
energy--momentum tensor of an electromagnetic wave in a dielectric. Minkowski's
tensor predicted an increase in the linear momentum of the wave on entering a
dielectric medium, whereas Abraham's tensor predicted its decrease. Theoretical
arguments were advanced in favour of both sides, and experiments proved
incapable of distinguishing between the two. Yet more forms were proposed, each
with their advocates who considered the form that they were proposing to be the
one true tensor. This paper reviews the debate and its eventual conclusion:
that no electromagnetic wave energy--momentum tensor is complete on its own.
When the appropriate accompanying energy--momentum tensor for the material
medium is also considered, experimental predictions of all the various proposed
tensors will always be the same, and the preferred form is therefore
effectively a matter of personal choice.Comment: 23 pages, 3 figures, RevTeX 4. Removed erroneous factor of mu/mu_0
from Eq.(44
Very slow surface plasmons: theory and practice
The paper is of a methodological character and has as a goal to give a brief
description of the concept of theory and practical application of very slow
optical plasmons. They exist on the metal-dielectric boundaries, namely, on
very thin metal films and fibers and as standing waves on metal spheres and
ellipsoids. The material presented in the paper features by widening the common
concepts of electromagnetic modes of various spaces, of the probability of
spontaneous emission, of creation of optical images, of the limits of optical
focusing, and of the photon linear momentum. All mentioned studies are
completed in recent years. The problem of the photon momentum in a dielectric
medium was the topic of irreconcilable disputes for 100 years starting in the
time of appearing of Minkowski and Abraham famous papers. Various practical
applications are surveyed: the experiments with a great intensification of an
atom spontaneous emission into a plasmonic field mode of a metal nanoparticle,
the experiments on focusing optical radiation into a spot that substantially
smaller than a diffraction limited spot, a so called near perfect Pendry lens
that produces the image with details that substantially smaller than defined by
diffraction, and lastly, the concept of hundredfold and more magnification of a
photon mechanical linear momentum in a plasmon. The work completed is supported
by RFBR, grants Nos 05-02-19647, 07-02-01328.Comment: 19 pages, 13 figure