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91.
A simple and efficient scheme based on a one-dimensional nanometric-thin cell filled with Rb and strong permanent ring magnets allows direct observation of the hyperfine Paschen-Back regime on the D(1) line in the 0.5-0.7 T magnetic field. Experimental results are perfectly consistent with the theory. In particular, with σ(+) laser excitation, the slopes of the B-field dependence of frequency shifts for all 10 individual transitions of (85,87)Rb are the same and equal to 18.6 MHz/mT. Possible applications for magnetometry with submicron spatial resolution and tunable atomic frequency references are discussed.  相似文献   
92.
We present an experimental measurement of the cooperative Lamb shift and the Lorentz shift using a nanothickness atomic vapor layer with tunable thickness and atomic density. The cooperative Lamb shift arises due to the exchange of virtual photons between identical atoms. The interference between the forward and backward propagating virtual fields is confirmed by the thickness dependence of the shift, which has a spatial frequency equal to twice that of the optical field. The demonstration of cooperative interactions in an easily scalable system opens the door to a new domain for nonlinear optics.  相似文献   
93.
Quantum diffusion equations with time-dependent transport coefficients are derived from generalized non-Markovian Langevin equations. Generalized fluctuation-dissipation relations and analytical formulas for calculating friction and diffusion coefficients in nuclear processes are obtained. The asymptotics of the transport coefficients and of the correlation functions are investigated. The problem of correlation decay in quantum dissipative systems is studied. A comparative analysis of diffusion coefficients for the harmonic and inverted oscillators is performed. The role of quantum statistical effects during passage through a parabolic potential barrier is investigated. Sets of diffusion coefficient assuring the purity of states at any time instant are found in cases of non-Markovian dynamics. The influence of different sets of transport coefficients on the rate of decay from a metastable state is studied in the framework of the master equation for reduced density matrices describing open quantum systems. The approach developed is applied to investigation of fission processes and the processes of projectile-nuclei capture by target nuclei for bombarding energies in the vicinity of the Coulomb barrier. The influence of dissipation and fluctuation on these processes is taken into account in a self-consistent way. The evaporation residue cross sections for asymmetric fusion reactions are calculated from the derived capture probabilities averaged over all orientations of the deformed projectile and target nuclei.  相似文献   
94.
We introduce a covering conjecture and show that it holds below ADR+“Θ is regular”ADR+Θ is regular”. We then use it to show that in the presence of mild large cardinal axioms, PFA   implies that there is a transitive model containing the reals and ordinals and satisfying ADR+“Θ is regular”ADR+Θ is regular”. The method used to prove the Main Theorem of this paper is the core model induction. The paper contains the first application of the core model induction that goes significantly beyond the region of AD++θ0AD++θ0<Θ.  相似文献   
95.
Polymer film based on 2-aminothiazole has been prepared at the surface of glassy carbon electrode via electropolymerization. The film has been modified via electrodeposition of rhodium particles. Hydrogen reduction has been observed at the so prepared composite films. Rhodium nanoparticles have been found uniformly distributed within the polymer matrix. Amount of the deposited metal depends on time of the electrode keeping in the rhodium salt solution. The prepared composite metal-polymers are highly heatresistant.  相似文献   
96.
Features of the effect of Faraday rotation (the rotation of the radiation polarization plane) in a magnetic field of the D 1 line in Cs atomic vapor in a nanocell with the thickness L varying in the range of 80–900 nm have been analyzed. The key parameter is the ratio L/λ, where λ = 895 nm is the wavelength of laser radiation resonant with the D 1 line. The comparison of the parameters for two selected thicknesses L = λ and λ/2 has revealed an unusual behavior of the Faraday rotation signal: the spectrum of the Faraday rotation signal at L = λ/2 = 448 nm is several times narrower than the spectrum of the signal at L = λ, whereas its amplitude is larger by a factor of about 3. These differences become more dramatic with an increase in the power of the laser: the amplitude of the Faraday rotation signal at L = λ/2 increases, whereas the amplitude of the signal at L = λ almost vanishes. Such dependences on L are absent in centimeter-length cells. They are inherent only in nanocells. In spite of a small thickness, L = 448 nm, the Faraday rotation signal is certainly detected at magnetic fields ≥0.4 G, which ensures its application. At thicknesses L < 150 nm, the Faraday rotation signal exhibits “redshift,” which is manifestation of the van der Waals effect. The developed theoretical model describes the experiment well.  相似文献   
97.
98.
Gaussian analysis (LinkFit program) was used to deconvolute overlapping absorption bands due to neutral and anionic forms of ascorbic acid (AA). It has been shown that the neutral form of AA predominates in aqueous solutions of AA containing dialkylsulfoxides (DASO) because a hydrogen-bonded complex forms between DASO and AA molecules.  相似文献   
99.
Sargsyan  A.  Pichler  G.  Sarkisyan  D. 《JETP Letters》2022,115(6):312-317
JETP Letters - The effect of the dielectric surface on the 39K D1 line (Fg = 1, 2 → Fe = 1, 2 transitions) at nanometer distances has been experimentally studied for the first time. A...  相似文献   
100.
Within the quantum diffusion approach, the capture of a projectile nucleus by a target nucleus is studied at bombarding energies above and below the Coulomb barrier. The effects of deformation of interacting nuclei and neutron transfer between them on the total and partial capture cross sections and the mean angular momentum of the captured system are studied. The results obtained for the 16O + 112Cd, 152Sm, and 184W; 19F +175Lu; 28Si +94,100Mo and 154Sm; 40Ca +96Zr; 48Ca+ 90Zr; and 64Ni +58,64Ni, 92,96Zr, and 100Mo reactions are in good agreement with available experimental data.  相似文献   
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