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Fig. 5. View of the dispersion curves
in an artificial opal calculated for
250 nm diameter silica globules (point
U
corresponds to the unitary polariton
n
=
−
1
)
Fig. 6. Basic scheme of the device for
detecting axions arising inside the Sun
or in the center of the Earth using a
photon crystal:
1
— closed vessel;
2
— magnets;
3
—
photon crystal;
4
— radiation detector;
5
—
amplifier;
6
— computer
“Cold” axions detection in the microwave spectral region.
The
problem of slow (“cool”) axion registration involves detecting the micro-
wave radiation in a strong magnetic field with the quantum energy
(0.001. . . 1.0 meV) coinciding with the energy of axions. With the imposi-
tion of a sufficiently strong external magnetic field (1. . . 10 Т), the
microwave photons must arise in the closed isolated cavity as a result
of the “cold” (slow) axions conversion into photons.
The possibility of experimental detection of axions the laboratory
using the Josephson effect [35–38] has recently been analyzed. A basic
diagram of a microwave radiation detector for the axion-photon conversion
using the non-stationary Josephson effect is shown in Fig. 7. Detection of
the so-called Shapiro steps in the volt-ampere characteristic provided
the opportunity of obtaining [39] the estimates of the axion rest energy
(0.11 meV) and of their density (0.05 GeV/сm
3
) in the surrounding space.
Other principal schematics of detectors of microwave photons arising
from the axion-photon conversion, based on sensitive detectors of micro-
wave radiation, are presented in Fig. 7,
b
,
c
. In this case a high-
Q
cavity
is supposed to be used consisting of two niobium mirrors (
8
,
10
), one of
which has a small hole. The cavity is placed in a cryostat for suppressing
ISSN 1812-3368. Herald of the BMSTU. Series “Natural Sciences”. 2014. No. 6
15