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The reasons for the discrepancies between the experimental data on the shape of long-wavelength continua near the 63P1 → 61S0 resonance line of a mercury atom in a xenon atmosphere obtained by different authors are analyzed. Calculations of spectral profiles for limiting cases of high and low densities of buffer gas atoms lead to the conclusion that the discrepancies are mainly due to the dependence of the rates of three-particle recombination and relaxation processes on the xenon density. Different types of a non-equilibrium or almost equilibrium (at high xenon concentrations) population of rovibrational states of a HgXe(A30+) excimer molecule are formed at different rates of these processes, which affects emission spectral profiles. [ABSTRACT FROM AUTHOR]

In the present review the results of the theoretical investigatation of the radiative lifetimes of the metastable ν'(1 P) states of CdAr, CdKr, HgAr, HgKr, HgXe quasimolecules as functions of the vibrational excitation degree are presented. The semiempirical interaction potential curves of Cd, Hg and rare gas (RG) atoms reconstructed from the available experimental data in the framework of the semiempirical method of quasimiolecular term analysis and the probabilities of the quasimolecular transitions which are the basis for the calculation of the radiative lifetimes are discussed. [ABSTRACT FROM AUTHOR]

A semiempirical method of analysis of quasi-molecular terms in conjunction with experimental potentials of interaction of Hg(6( P)) atoms with Ar, Kr, and Xe atoms are used to obtain the Hg(6 P)-Ar, Kr, Xe interaction potential, which are applied to calculating the radiative lifetimes of the v′1( P) states of the HgAr, HgKr, and HgXe molecules and the probabilities of the v′1( P)− v″0( S) transitions. [ABSTRACT FROM AUTHOR]

By using the modified method of the Fermi pseudopotential and the effective Hamiltonian method, a multiconfiguration calculation of the potential curves is performed for the Hg(6[sup 1, 3]P[sub J]) + He and Hg(7[sup 1, 3]S[sub J]) + He interactions in the region of interatomic separations R ≥ 5a[sub 0]. In this calculation, the interactions of different excited configurations and the spin-orbit coupling of singlet and triplet states were taken into account. The Hg[sup +] + He ion-atom interaction potential was obtained by the nonempirical configuration interaction method MRD-CI with the use of the relativistic effective core potential (RECP) for the Hg atom. Based on the calculated potential curves and the transition dipole moments, the process of radiative decay of the Hg(6 ³P[sub 2]) metastable state in collisions with He atoms is considered and the temperature dependence of the rate constant is calculated. [ABSTRACT FROM AUTHOR]

Despite significant theoretical efforts devoted to studying the interaction between quantized light modes and matter, the so-called ultrastrong coupling regime still presents significant challenges for theoretical treatments and prevents the use of many common approximations. Here we demonstrate an approach that can describe the dynamics of hybrid quantum systems in any regime of interaction for an arbitrary electromagnetic (EM) environment. We extend a previous method developed for few-mode quantization of arbitrary systems to the case of ultrastrong light-matter coupling, and show that even such systems can be treated using a Lindblad master equation where decay operators act only on the photonic modes by ensuring that the effective spectral density of the EM environment is sufficiently suppressed at negative frequencies. We demonstrate the validity of our framework and show that it outperforms current state-of-the-art master equations for a simple model system, and then study a realistic nanoplasmonic setup where existing approaches cannot be applied.

Optical control is achieved on the excited state energy transfer between spatially separated donor and acceptor molecules, both coupled to the same optical mode of a cavity. The energy transfer occurs through the formed hybrid polaritons and can be switched on and off by means of ultraviolet and visible light. The control mechanism relies on a photochromic component used as donor, whose absorption and emission properties can be varied reversibly through light irradiation, whereas in-cavity hybridization with acceptors through polariton states enables a 6-fold enhancement of acceptor/donor contribution to the emission intensity with respect to a reference multilayer. These results pave the way for synthesizing effective gating systems for the transport of energy by light, relevant for light-harvesting and light-emitting devices, and for photovoltaic cells., Competing Interests: Conflict of interest: Authors state no conflicts of interest., (© 2024 the author(s), published by De Gruyter, Berlin/Boston.)

Resonant interaction between excitonic transitions of molecules and localized electromagnetic field allows the formation of hybrid light-matter polaritonic states. This hybridization of the light and the matter states has been shown to significantly alter the intrinsic properties of molecular ensembles placed inside the optical cavity. Here, we have observed strong coupling of excitonic transition in a pair of closely located organic dye molecules demonstrating an efficient donor-to-acceptor resonance energy transfer with the mode of a tuneable open-access cavity. Analysing the dependence of the relaxation pathways between energy states in this system on the cavity detuning, we have demonstrated that predominant strong coupling of the cavity photon to the exciton transition in the donor dye molecule can lead not only to an increase in the donor-acceptor energy transfer, but also to an energy shift large enough to cause inversion between the energy states of the acceptor and the mainly donor lower polariton energy state. Furthermore, we have shown that the polariton-assisted donor-acceptor chromophores' role reversal or "carnival effect" not only changes the relative energy levels of the donor-acceptor pair, but also makes it possible to manipulate the energy flow in the systems with resonant dipole-dipole interaction and direct energy transfer from the acceptor to the mainly donor lower polariton state. Our experimental data are the first confirmation of the theoretically predicted possibility of polariton-assisted energy transfer reversal in FRET systems, thus paving the way to new avenues in FRET-imaging, remote-controlled chemistry, and all-optical switching., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Controlling spontaneous emission by modifying the local electromagnetic environment is of great interest for applications in optoelectronics, biosensing and energy harvesting. Although the development of devices based on one-dimensional porous silicon photonic crystals with embedded luminophores is a promising approach for applications, the efficiency of the embedded luminophores remains a key challenge because of the strong quenching of the emission due to the contact of the luminophores with the surface of porous silicon preventing the observation of interesting light-matter coupling effects. Here, we experimentally demonstrate an increase in the quantum dot (QD) spontaneous emission rate inside a porous silicon microcavity and almost an order of magnitude enhancement of QD photoluminescence intensity in the weak light-matter coupling regime. Furthermore, we have demonstrated drastic alteration of the QD spontaneous emission at the edge of the photonic band gap in porous silicon distributed Bragg reflectors and proved its dependence on the change in the density of photonic states.

The article is devoted to the history of forming and developing of the 7th Central Policlinic of Strategic Missile Forces, which the 22nd of January 2010 has it's 50th anniversary. The article presents the results of activity of the policlinic in promotion of health of servicemen, work, effectuating by policlinic staff in a sphere of reclaiming and involving of modern high-informative methods of diagnostics and treatment, there were given main of them.