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Here

n

0

,

n

0

,

m

b

are occupation numbers for the respective fields. The energy

and quasimomentum conservation laws for different elementary processes

of the photon-boson conversion take the following form

~

ω

0

=

~

ω

0

+

~

ω

;

~

~k

0

=

~

~k

0

+

~

~k

;

~

ω

0

+

~

ω

=

~

ω

0

;

~

~k

0

+

~

~k

=

~

~k

0

;

~

ω

0

=

~

ω

0

(

para

) +

~

ω

(

γ

);

~

~k

0

(

γ

) =

~

~k

0

(

para

) +

~

~k

(

γ

);

~

ω

0

+

~

ω

=

~

ω

0

(

para

);

~

~k

0

(

γ

) +

~

~k

(

γ

) =

~

~k

0

(

para

);

~

ω

0

=

~

ω

0

(

axi

) +

~

ω

;

~

~k

0

(

γ

) =

~

~k

0

(

axi

) +

~

~k

(

m

);

~

ω

0

+

~

ω

=

~

ω

0

(

axi

);

~

~k

0

(

γ

) +

~

~k

(

m

) =

~

~k

0

(

axi

);

~

ω

0

(

axi

) =

~

ω

0

;

~

~k

0

(

axi

) =

~

~k

0

;

~

ω

0

=

~

ω

0

(

axi

);

~

~k

0

(

γ

) =

~

~k

0

(

axi

);

(8)

~

ω

0

+

~

ω

0

=

~

ω

0

(

para

);

~

~k

0

(

γ

) +

~

~k

0

(

γ

) =

~

~k

0

(

para

);

~

ω

0

(

para

) =

~

ω

0

+

~

ω

0

;

~

~k

0

(

para

) =

~

~k

0

(

γ

) +

~

~k

0

(

γ

)

.

(9)

When excitation radiation is low (

n

0

1

), spontaneous photon-boson

conversion processes take place. When the radiation is more intensive

(

n

0

1

), induced processes may take place. In particular, when excitation

radiation has high intensity, the induced Raman scattering takes place in

the material media, when photons of the excitation radiation converse into

scalar bosons of the material medium with a high transformation coefficient

(

0

.

1

). Diagrams of the experimental installations used for the induced

Raman scattering analysis are presented in Fig. 7 [11, 16, 17].

The induced Raman scattering spectra in calcite monocrystals, in

organic compound POPOP powder, and liquid nitrogen (

N

2

molecule)

during the impulse laser excitation are shown in Fig. 8. In the case of

nitrogen, a multi-stage conversion process takes place and both Stokes and

anti-Stokes processes are registered.

Interferograms of the induced boson light scattering spectrum by the

oscillations of quartz globules of both the photon crystal and spectrum of

ruby laser generation with the emission line width of about 0.01 cm

1

produced with the help of the experimental installation presented in

Fig. 7,

b

, are shown in Fig. 9. Comparison of these spectra shows that

in the spectrum of the induced boson scattering there is an additional ring

system corresponding to the Stokes shift

Δ

ν

0

.

3

cm

1

.

Let us note that coherent excitation of the totally symmetrical modes

(scalar bosons) during the induced Raman scattering may result in

the decay of scalar (“mechanical”) bosons into two entangled photons

from microwave or radiowave range (the dynamic Casimir effect). Such

44

ISSN 1812-3368. Herald of the BMSTU. Series “Natural Sciences”. 2015. No. 1