We investigate analytically and numerically the nonstationary circuit QED setup in which N independent qubits interact with a single mode of the Electromagnetic field confined in a resonator. We ...consider the harmonic time modulation of some parameter (atomic transition frequency or the atom-field coupling strength) and derive the unitary dynamics up to the second order in the modulation depth for N = 1 and N > 1 . It is shown that all the resonant phenomena that occur for modulation frequencies ∼ 2 0 (where 0 is the cavity frequency) also occur for the halved frequencies. However, in the latter case the associated transition rates are significantly smaller and the modulation of the coupling strength is less effective. The transition rates are evaluated explicitly and the prospects of employing the second-order resonances in the phenomena related to the dynamical Casimir effect are examined.
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 consider the semiclassical Rabi model in the presence of Markovian dissipation and study the system dynamics in the vicinity of the three-photon resonance, when the laser frequency is nearly one ...third of the atomic transition frequency. Closed analytic expressions are derived for the system density operator, in excellent agreement with exact numeric results. We also study semi-analytically the dynamics of the quantum Rabi model for the initial coherent state, and show how the semiclassical behavior emerges from the quantum three-photon Rabi oscillations as the amplitude of the coherent state increases.
•Analytical expressions are derived for the dynamics of dissipative semiclassical Rabi model near the three-photon resonance.•Semi-analytical method is presented to describe the dynamics of the quantum Rabi model near the three-photon resonance.•Emergence of the semiclassical behavior from the quantum one is illustrated for the three-photon Rabi oscillations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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
Dynamical Casimir effect (DCE) is the name assigned to the process of generating quanta from vacuum due to an accelerated motion of macroscopic neutral bodies (mirrors) or time-modulation of cavity ...material properties, as well as the simulation of such processes. Here I review the theoretical results on the detection of DCE using intracavity quantum detectors, such as multi-level atoms, atomic networks and harmonic oscillators. I also stress the mathematical equivalence of this problem to the physics of optical parametric oscillators interacting with atoms or quantum wells, studied in quantum nonlinear optics.
We study the evolution of the most general initial Gaussian packet with nonzero correlation coefficient between the coordinate and momentum operators in the presence of a repulsive delta-potential ...barrier, using the known exact propagator of the time-dependent Schrödinger equation. For the initial packet localized far enough from the barrier, we define the transmission coefficient as the probability of discovering the particle in the whole semi-axis on the other side of the barrier. It appears that the asymptotical transmission coefficient (calculated in the large time limit) depends on two dimensionless parameters: the normalized ratio of the potential strength to the initial mean value of momentum and the ratio of the initial momentum dispersion to the initial mean value of momentum. For small values of the second parameter, the result is reduced to the well-known formula for the transparency of the delta barrier, obtained in the plane-wave approximation by solving the stationary Schrödinger equation. For large values of the second parameter, the transmission coefficient can be much larger than that calculated in the plane-wave approximation. For a fixed initial spread of the packet in the coordinate space, the initial correlation coefficient influences the transparency of the barrier only indirectly, through the increase in the initial momentum dispersion.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The galaxy SBS1001+555 is studied as an object from the base sample in our program for study of evolutionary processes of star formation in galaxies. The work is based on the results of panoramic ...spectroscopy of the central part, which is the activity zone of the galaxy with its main star formation region, which we denote by A. The observations employ an MPFS (multipupil fiber spectrograph) on the 6-m telescope of the Special Astrophysical Observatory (SAO) of the Russian Academy of Sciences (RAS) to yield a 635-725 nm spectral band with a dispersion of 0.76 Å/pixel. Besides the most intense Balmer Hα emission line, the resulting integrated spectrum includes the HeI 6678 and HeI 7065 lines, forbidden lines of nitrogen, sulfur, and argon, NII 6548, 6583, SII 6716, 6731, and ArIII 7136 Å, and more than ten faint lines of neutral and singly ionized iron and neon, FeI 6824, 6837, 7447, 7453, and 7544, NeI 7245 and 7544, FeII 7682 and 7687, and NeII 7213 Å. A detailed analysis is made of the twodimensional distributions of the intensities, radial velocities, and other parameters over the field of view in Hα. Besides A, the largest and brightest HII region, three small regions A1, A2, and A3 have been identified, which form a common structure with A. One of the secondary regions, A1, is revealed with a condensation that stands out in an IRAC 4.5 μm image. The values of the main parameters in their peaks are taken to be the numerical characteristics of the HII regions, and those of the integral formations are taken to be the equivalent radius, luminosity, and star-formation rate, Req, L(Hα), and SFR(Hα). The data shown here, in particular, are indicative of active processes immediately associated with the brightest source of visible radiation in SBS1001+555 and the development of a star-formation structure around it.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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