It was predicted some time ago that the cavity dynamical Casimir effect (generation of photons from the initial vacuum state in a cavity with moving walls) might be observed if a boundary vibrates at ...the double frequency of some selected cavity mode. However, to register the created photons one has to couple the cavity mode with some detector. Considering the harmonic oscillator model of a detector, we analyze how different coupling regimes can affect the statistics of the created quanta.
The complex (dpp-bian)SiCl
2
(
1
) was synthesized by the reaction of the free 1,2-bis(2,6-diisopropylphenyl)iminoacenaphthene (dpp-bian) ligand with Si
2
Cl
6
. Despite the presence of the dpp-bian ...dianion, complex
1
is inert toward heteroallenes. An attempt to increase the reactivity of complex
1
by abstracting a halogen atom from (dpp-bian)-SiCl
2
by the treatment with AlCl
3
led to the formation of the cationic complex (dpp-bian)SiCl
2
Al
2
Cl
7
(
2
). The iron μ-silylene complex (dpp-bian)Si{FeCp(CO)}
2
(μ-CO) (
4
) was synthesized by the reaction of silylene (dpp-bian)Si (
3
) with 0.5 mol. equiv. of CpFe(CO)
2
2
. The reaction of
4
with phenyl isothiocyanate afforded sulfide (dpp-bian)-SiS
2
(
5
). The new compounds were characterized by IR (
2, 4, 5
), EPR (
2
), and multi-nuclear NMR (
4
) spectroscopy and by elemental analysis. The molecular structures of complexes
2, 4
, and
5
were established by X-ray diffraction.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We study two families of four-photon superpositions of the Fock states: even vacuum squeezed states (EVSS) and orthogonal-even coherent states (OECS). These families are distinguished due to several ...properties: for certain values of parameters, they give the fourth-order uncertainty products close to the known minimal value (which is lower than for the Gaussian states); they have equal dimensionless values of the second- and fouth-order moments of the coordinate and momentum for all values of parameters; they possess zero covariances for all values of parameters. Since these states are obviously non-Gaussian, we consider them as good candidates to compare several different measures of non-Gaussianity proposed by different authors for the past fifteen years. The reference Gaussian states in all examples are thermal states dependent on a single parameter (an effective temperature or the coordinate variance). We analyze the measures based on the normalized Hilbert–Schmidt distance and the relative entropy (introduced by Genoni–Paris–Banaszek), the fidelity measure (Ghiu–Marian–Marian) and its logarithmic analog (Baek–Nha), as well as the Mandilara–Karpov–Cerf “Gaussianity parameter”. These measures are compared with the kurtosis of the coordinate probability density and with the non-Gaussian behavior of the Wigner function.
The reaction of (dpp-bian)Yb(DME)
2
with one equivalent of dpp-bian and one equivalent of potassium or sodium gave the ate complexes (dpp-bian)
2
YbK(DME)
4
and (dpp-bian)
2
YbNa(THF)
6
. The ...reaction of (dpp-bian)YbI(DME)
2
with potassium cyclopentadienide (CpK) led to the complex {(dpp-bian)CpYb(μ-Cp)· K(Et
2
O)
2
}
2
(μ-Cp)
2
Yb(THF)
2
. In all three compounds, the redox-active dpp-bian exhibits a dianionic state. Yb
3+
cations in the prepared compounds determine their paramagnetism. Despite this, resolved
1
H and
13
C NMR spectra were obtained for (dpp-bian)
2
YbK(DME)
4
and (dpp-bian)
2
YbNa(THF)
6
in THF-
d
8
, which made it possible to assign observed signals. The new compounds were characterized by IR and NMR spectroscopy and elemental analysis (C, H, N). The molecular structure of the prepared complexes was determined by X-ray diffraction
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We study theoretically the nonstationary circuit QED system in which the artificial atom transition frequency, or the atom-cavity coupling, have a small periodic time modulation, prescribed ...externally. The system formed by the atom coupled to a single cavity mode is described by the Rabi Hamiltonian. We show that, in the dispersive regime, when the modulation periodicity is tuned to the 'resonances', the system dynamics presents the dynamical Casimir effect, resonant Jaynes-Cummings or resonant Anti-Jaynes-Cummings behaviors, and it can be described by the corresponding effective Hamiltonians. In the resonant atom-cavity regime and under the resonant modulation, the dynamics is similar to the one occurring for a stationary two-level atom in a vibrating cavity, and an entangled state with two photons can be created from vacuum. Moreover, we consider the situation in which the atom-cavity coupling, the atomic frequency, or both have a small non-periodic time modulation, and show that photons can be created from vacuum in the dispersive regime. Therefore, an analog of the dynamical Casimir effect can be simulated in circuit QED, and several photons, as well as entangled states, can be generated from vacuum due to the anti-rotating term in the Rabi Hamiltonian.
This study is aimed at identifying the preliminary results of Kazakhstan’s foreign trade with countries that have agreements on economic cooperation with the Eurasian Economic Union.
Aim
. ...Identification the emergence of effects for Kazakhstan’s foreign trade from agreements with the EAEU partner states.
Tasks
. Analyze the indicators of Kazakhstan’s foreign trade with states that have preferential modes of cooperation with the EAEU, compare these indicators of the validity period of the relevant agreements with previous periods and with the parameters of Kazakhstan’s foreign trade as a whole, assess the results of foreign trade during the period of validity of agreements on economic cooperation.
Methods
. In this work, we used the methods of time series analysis and comparative analysis.
Results
. The study showed that in most cases, the intensity of Kazakhstan’s mutual trade with countries that have preferential regimes of cooperation with the EAEU has significantly increased after the conclusion of agreements. Trade of Kazakhstan with the only country with a relatively long history of the current free trade agreement, Vietnam, showed significant growth during this period, many times higher than the general indicators of foreign trade. The outstripping growth in trade with the considered countries occurs, as a rule, due to an increase in Kazakhstani exports, which has a positive effect on foreign trade as a whole and has a positive effect on the indicators of the trade and balance of payments. The cumulative effect for Kazakhstan’s foreign trade from increasing trade with the EAEU partner countries is quite large and is measured by an annual increase in trade turnover at the level of more than $ 650 million, and an increase in exports in the amount of slightly less than $ 1 billion.
Conclusion
. The preliminary results of Kazakhstan’s foreign trade with the EAEU partner countries are positive and confirm the existence of potential for further cooperation through the conclusion of new trade and other agreements with other states.
We study the influence of fluctuations in periodic motion of boundaries of an ideal three-dimensional cavity on the rate of photon generation from vacuum due to the nonstationary Casimir effect.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We consider the problem of minimization of products of mean values of the high powers of operators x and p. From this point of view, we study several two-term superpositions of the Fock states, as ...well as three popular families of infinite superpositions: squeezed states, even/odd coherent states, and orthogonal even coherent states (or compass states). The new element is the analysis of products of the corresponding (co)variances and the related generalized (Robertson-Schrödinger) intelligent states (RSIS). In particular, we show that both Fock and pure Gaussian homogeneous states are RSIS for the fourth powers (but not for the sixth ones). We show that lower bounds of the high-order uncertainty products can be significantly below the vacuum values. In this connection, the concept of significant and weak high-order squeezing is introduced.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The article analyzes trends and factors in the dynamics of Kazakhstan’s mutual trade within the EAEU with an emphasis on imports and trade deficits. The aim is to identify the relationship between ...changes in the absolute and relative values of these parameters and the country’s membership in Eurasian integration organizations and with more general external factors. To achieve the aim, the volume, dynamics and share of imports and trade deficits are analyzed in the context of changes in the purchasing power of the population, world oil prices and volumes of Kazakhstan’s foreign trade with the rest of the world. Research methods: comparative analysis of time series, structural and correlation analysis. As a result of the analysis, a tendency was revealed for an increase in the imbalances in mutual trade of Kazakhstan during the EAEU existence, which, however, are far from historical highs, which does not allow us to conclude that there is a causal relationship between the country’s membership in this association and the aggravation of problems in mutual trade. On the other hand, it was revealed that significant shifts in the share of imports from the EAEU countries to Kazakhstan and the resulting changes in the trade deficit occurred during periods of significant shifts in the purchasing power of the population and are inversely proportional. The analysis made it possible to draw the following conclusions: the relative indicators of imports and trade deficits do not show growth after the creation of the EAEU; the main factor in the change in the share of imports to Kazakhstan from the EAEU is the dynamics of the currency equivalent of household income — the increase in the share of imports from the EAEU occurs during periods of decline in household income, and its decline during periods of their growth; the currency equivalent of income in Kazakhstan is closely correlated with world oil prices, that is, the dependence of the parameters of imports from the EAEU and the trade deficit is due to a more general factor in the external economic situation that affects the purchasing power of the population and business.
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