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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