12 / 17
Fig. 10. Spectra of the induced Raman
scattering in lithium niobate by longitudinal
(
a
) and transverse (
b
) polaritons for two
scattering geometries ((p) corresponds to
polariton wave excitation, A
1
TO corresponds
to transverse polar phonon scattering)
Fig. 11. Diagram of a wall penetration
by light from area
a
to area
b
in the
magnetic field
line corresponds to the magnetic field. Such a process (the Primakov effect)
is classified as the process of a wall penetration by light. Fig. 12 shows
installations for implementation of the photon-axion conversion in vacuum
in a strong magnetic field, which conversion laws correspond to equations
(8). Several teams of scientists have recently made experimental attempts
to track this effect in vacuum [18–27]. Selection rules allow direct photon-
axion conversion in a constant magnetic field in vacuum, but the probability
of this spontaneous process is not high. Let us note that the use of powerful
continuous wave lasers, strong magnetic field (10 Tl), and resonators in the
form of interferometers (Fig. 12,
b
) did not provide a reliable signal level on
the detectors used in the researches [18–27]. Thus, a reliable experimental
confirmation of the effect of a wall penetration by light has not been
provided so far.
Thereby, the author proposes that photon-axion and photon-paraphoton
conversion should be performed not in vacuum but in a material medium.
Respective synchronism conditions (energy and quasi-momentum conser-
vation laws) for such conversion processes in a material medium could
be provided by exciting radiation in the form of unitary polaritons for
which the equality
n
2
= 1
is true. As it was mentioned above, unitary
polaritons are present at certain frequencies in dielectric media and in
photon crystals. Experimental installations for different photon-boson
conversion implementations in material media are shown in Fig. 13.
It can be assumed that in material media, the probability of photon-
boson conversion should grow considerably due to photon-phonon and
photon-photon interactions in dielectric media, and during the localization
ISSN 1812-3368. Herald of the BMSTU. Series “Natural Sciences”. 2015. No. 1
47