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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