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1.
A self-consistent problem of interaction of two dipole atoms separated by an unrestricted distance with the field of a quasi-resonance
light wave was solved on the assumption that the investigated atoms are Lorentz linear oscillators and the polarizing fields
inside the system consist of the Coulomb and the retarded parts. The solution obtained was investigated for the case where
the atoms have the same polarizability and the distance between them is much smaller than the length of the external light
wave. Formulas for the electric fields inside a small object and outside it have been obtained. It is shown that inside a
small two-atom object there can take place longitudinal and transverse optical vibrations accompanied by corresponding dispersion
effects depending on the interatomic distance and the angle between the axis of the system and the direction of propagation
of the external light wave. The field outside the small object in the wave zone is linearly polarized when the external wave
has linear polarization. However, the direction of polarization of the corresponding waves is largely determined by their
frequency. It is also shown that the amplitude of the field outside the small object in the wave zone depends greatly on the
frequency of the external field and the interatomic distance. The effects observed are considered as a near-field effect in
optics of small objects. This phenomena makes it possible to investigate the structure of small objects with the use of optical
radiation.
Ul'yanovsk Branch of the Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 48 Goncharov Str., Ul'yanovsk,
432700, Russia; e-mail: gadomsky@quant.univ.simbirsk.su. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 6,
pp. 765–770, November–December, 1999. 相似文献
2.
We have solved a self-consistent problem on interaction of two dipole atoms located at an arbitrary distance from each other
with the field of a quasiresonance light wave, whose intensity is sufficient for the system to manifest nonlinear properties.
The atoms are considered as two-level systems described by means of Bloch optical equations, while the field inside of the
system includes both Coulomb and retarded parts. We consider a situation where atoms are identical and the distance between
them is much smaller than the length of an outer light wave. The distribution of an electric field both inside of a small
object and outside of it is found numerically. It is shown that the amplitude of the electric field in a wave zone depends
substantially on the frequency of the external field and interatomic distance, while the field distribution differs from the
field pattern of an electric dipole. At definite values of the external field intensity an optical multistability is a feature
of the system under investigation. We have elucidated the conditions under which the multistability is manifested in the present
system. The results obtained are considered as the near-field effect in the optics of small objects, which makes it possible
to investigate the structure of small objects by means of optical radiation.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 3, pp. 375–378, May–June, 2000.
The present work was supported by the Russian Foundation for Fundamental Research (grant 98-02-16035) and by a grant from
the Federal Purpose-Oriented Program “Integration.” 相似文献
3.
A. S. Kadochkin 《Journal of Applied Spectroscopy》2007,74(4):552-560
We have solved the problem in which a thin metal wafer (probe) with a nanohole interacts with the flat surface of a metastructured
film consisting of metal nanoparticles in an external optical radiation field. Nanoparticles are considered as two-level atomic
systems. This interaction of the wafer-probe and the flat surface in the external optical radiation field gives rise to optical
near-field resonance, the frequency of which differs significantly from the natural frequencies of two-level atoms in the
medium and the probe. The fields inside and outside the probe and metastructured film are calculated in the near-field and
far-field zones. The maximum resolution, which is achievable in the suggested scheme of near-field optical microscopy, can
reach about 10 nm.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 4, pp. 499–506, July–August, 2007. 相似文献
4.
We have solved a boundary-value problem for a ball probe interacting with a flat dielectric surface in an external optical radiation field. This interaction gives rise to the optical size resonance at frequencies significantly different from the natural frequencies of two-level atoms both in the medium and in the probe with allowance for the local field corrections. These resonances depend significantly on the distance from the probe center to the surface, on the ball probe size, on the concentration of two-level atoms in the probe and in the medium, on the spectral line width, and on the atomic inversion. The field strengths inside and outside the ball probe and a semiinfinite dielectric medium have been calculated in the near-field and wave zones. It is shown that the proposed electrodynamic theory of optical near-field microscopy agrees with the results of experimental measurements. 相似文献
5.
A. S. Shalin 《Journal of Applied Spectroscopy》2006,73(5):719-726
The integrodifferential equation method is used to study the spectrum of a nanoparticle colloid for the example of interaction
of three arbitrarily arranged dielectric particles made up of nonresonant atoms (the eigenfrequency of the transition is far
from the emission frequency) with incorporated barium atoms in an external optical radiation field. The effect on the light-scattering
properties of a nanosphere in the ensemble of its distant “neighbors” is studied; an additional peak associated with them
is observed as a frequency close to the resonance for an isolated nanosphere, which under certain conditions has higher intensity
than the main peak corresponding to optical near-field resonance in a two-particle system. The dependence of the spectrum
of the nanosized system on the geometric structure is studied, and it is shown that very precise tuning of the resonance frequency
is possible by varying the angular distribution of the particles.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 5, pp. 641–646, September–October, 2006. 相似文献
6.
V. M. Zhuravlev 《Russian Physics Journal》2000,43(1):6-10
An approach to constructing electrodynamics with an integer charge based on its topological interpretation is considered in
the present paper. The condition that changes are integers is shown to endow the space itself with a variable permittivity.
It is demonstrated that the concept suggested here solves the main problems of electrodynamics associated with point charges
and provides a simple topological classification of field structures compared to that of the main elementary particles, including
baryons. Electrodynamics equations of integer-charge fields are derived.
Ul'yanovsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 8–13, January, 2000. 相似文献
7.
8.
A. S. Rudyi 《Technical Physics》1998,43(3):342-344
Two-phase states of equilibrium of a thin superconducting film carrying a current under conditions of convective heat exchange
at the free surface of the film are studied. It is shown that for a classical superconductor the two-phase state of the film
remains a single-front state over a wide range of parameters of the system. For high-T
c superconductors there exists a maximum value of the Steckl number above which weakly nonequilibrium stationary states can
only be multifront states. The solutions of the boundary-value problem modeling a two-front state of equilibrium are investigated,
and the conditions under which they obtain are examined.
Zh. Tekh. Fiz. 68, 84–87 (March 1998) 相似文献
9.
A. M. Basharov A. I. Maimistov S. O. Elyutin 《Journal of Experimental and Theoretical Physics》1999,88(1):16-23
The problem of the interaction of an ultrashort optical pulse and a thin film of resonant atoms under the conditions of two-photon
absorption, third-harmonic generation, and the inverse effect of the latter on the pump pulse via Raman scattering is studied.
The fact that the field acting on an atom differs from the macroscopic field in the film is also taken into consideration.
It is shown that the polarization of the film undergoes dynamic relaxation even in the absence of irreversible relaxation,
suppressing Rabi oscillations and establishing stationary values of the populations of the resonant energy levels and of the
polarization of the film at the pump and the third-harmonic frequencies.
Zh. éksp. Teor. Fiz. 115, 30–42 (January 1999) 相似文献
10.
An analysis is made of some general laws governing a new physical effect, i.e., the spontaneous penetration of particles (atoms,
C60 molecules) adsorbed on a two-dimensional graphite film on a metal (Ir, Re, Pt, Mo,...) to beneath the graphite film (intercalation).
It is shown that atoms having low ionization potentials (Cs, K, Na) intercalate a two-dimensional graphite film on iridium
at T=300–400K with an efficiency χ≈0.5, accumulating beneath the film to a concentration of up to a monolayer. Atoms having high ionization potentials (Si,
Pt, Ni, C, Mo, etc.) intercalate a two-dimensional graphite film on iridium at T≈1000K with an efficiency, χ≈1, forming beneath the film a thick intercalate layer which is strongly bonded chemically to the metal substrate but is probably
weakly bonded to the graphite monolayer by van der Waals forces. The presence of a graphite “lid” impeding the escape of atoms
from the intercalated state up to record high temperatures T∼2000K leads to superefficient diffusion (with an efficiency close to one) of various atoms (Cs, K) into the bulk of the substrate
(Re, Ir).
Zh. Tekh. Fiz. 69, 72–75 (September 1999) 相似文献
11.
12.
A. S. Shalin 《Russian Physics Journal》2006,49(8):791-801
The optical properties of a colloid consisting of nanoparticles are investigated on the example of interaction of three dielectric
particles consisting of nonresonant atoms (whose natural transition frequencies are far from the radiation frequency) with
interstitial barium atoms in the field of external optical radiation. On the basis of integrodifferential equations, expressions
for the electric and magnetic fields in the wave zone are derived. The influence of distant neighbors in the ensemble on the
light-scattering properties of a nanoparticle is considered, and the condition of applicability of the frequently used two-particle
approximation is obtained. The spectrum of the system is investigated, and an additional resonant peak at the natural frequency
of the isolated particle caused by the distant neighbor is established. Under some specific conditions, the additional peak
intensity may exceed the main peak intensity of the optical near-field resonance in the two-particle system.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 3–11, August, 2006. 相似文献
13.
V. V. Semenov 《Journal of Applied Spectroscopy》1998,65(6):871-878
A computation is carried out for light-induced shifts in the frequency of a multiphoton radiooptical SHF resonance in alkali
atoms on the basis of the quantum formalism of spherical tensors. The components of a light-induced shift in frequency at
magneto-independent 0–0– and 1,–1-transitions in87Rb atoms under the conditions of isotopic filtration of the resonance light of pumping are calculated. The difference between
the temperatures of a filter cell is discovered at which the point of zero shift in the frequency of radiooptical resonance
is attained. The components of the light-induced shift of frequency in optically oriented87Rb and133Cs atoms are compared in the absence of collisional reorientation in excited state. The prevailing role of the tensor component
of light-induced shift in pumping by the D1-line of a head doublet and the effect of the orientational dependence of the frequency of a multiphoton resonance on change
in the sign of the pumping source radiation polarization are noted.
St. Petersburg State Polytechnical University, 29 Politekhnicheskaya Str., St. Petersburg, 195251, Russia. Translated from
Zburnal Prikladnoi Spektroskopii, Vol. 65, No. 6, pp. 832–838, November–December, 1998. 相似文献
14.
V. V. Klimov 《JETP Letters》1998,68(8):641-645
The linewidth for an atom located near an ideally conducting tip or inside a conical cavity in an ideal conductor is analyzed.
It is shown that the effect of the tip decreases as its opening angle decreases. At the same time, the linewidth for an atom
in a conical cavity can strongly increase or strongly decrease, depending on the position of the atom and the opening angle
of the cavity. The results obtained could be helpful in designing spectrally-selective near-field nanoscopes.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 8, 610–613 (25 October 1998) 相似文献
15.
The boundary problem of nonlinear optics was investigated for a trial wave reflected (refracted) by an excited region of a
nonlinear medium considered as a system of multilevel atoms in the spectrum of which there are two closely-spaced energy levels
excited by a powerful quasi-resonant radiation. It is shown that under interference conditions of the atomic states in the
field of the trial and resonance waves there exist three types of waves: an inverse wave and two polarization waves. By way
of extension of the Ewald-Oseen procedure to this case a formula for the complex refractive index of a nonlinear medium for
the three types of waves as well as a generalized extinction theorem have been obtained. It is shown that the trial wave can
be amplified without inversion of the interfering atomic states and that the refractive index can be markedly changed at certain
concentrations of atoms in the medium. General formulas for the amplitudes of the reflected and refracted waves have been
obtained.
Ul’yanovsk State University, 42, Tolstoi Str., Ul’yanovsk, 432700, Russia. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 65, No. 4, pp. 568–575, July–August, 1998. 相似文献
16.
An exact solution is obtained and a problem of waveguide light propagation in a scalar asymmetric four-layer waveguide with
an absorbing coating layer is analyzed numerically. The periodicity of modal characteristics with change in the coating layer
thickness is established. The feasibility of achieving a single-mode light propagation regime at the expense of the absorbing
coating layer is demonstrated.
Ul'yanovsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 79–85, July, 2000. 相似文献
17.
We construct and study an analytical solution of the boundary-value problem for the radiation field of a small spheroidal
antenna located in free space and surrounded by a thin shell of cold homogeneous isotropic plasma. Conditions for a resonant
increase in the field in free space as a function of the plasma-shell thickness with the variation in the spheroidal-antenna
shape are studied. It is shown that the plasma shell has the largest effect on the radiation field of a strongly prolate spheroidal
antenna.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 3, pp. 246–257, March 2006. 相似文献
18.
This paper reports on a study by angle-resolved photoelectron and low-energy electron energy loss spectroscopy of graphene
monolayers, which are produced by propylene cracking on the Ni(111) surface, followed by intercalation of Cu, Ag, and Au atoms
between the graphene monolayer and the substrate, for various thicknesses of deposited metal layers and annealing temperatures.
It has been shown that the spectra of valence-band π states and of phonon vibrational modes measured after intercalation become
similar to those characteristic of single-crystal graphite with weak interlayer coupling. Despite the strong coupling of the
graphene monolayer to the substrate becoming suppressed by intercalation of Cu and Ag atoms, the π state branch does not reach
at the K point of the Brillouin zone the Fermi level, with the graphene coating itself breaking up partially to form graphene domains.
At the same time after intercalation of Au atoms, the electronic band structure approaches the closest to that of isolated
graphene, with linear π-state dispersion near the K point of the Brillouin zone, and the point of crossing of the filled, (π), with empty, (π*), states lying in the region of
the Fermi level, which makes this system a promising experimental model of the quasi-free graphene monolayer. 相似文献
19.
A magnesium–nickel (Mg–Ni) film with a palladium (Pd) overcoat is switchable between a conducting metallic state and a semiconducting
state through hydridation and dehydridation processes. The Pd overcoat is added to suppress possible oxidation of the alloy
layer. However, some Pd and oxygen (O) atoms are still able to diffuse into the alloy layer, such that the distributions of
elemental and phase compositions along the direction of depth are quite complicated. In this work, we propose a method to
obtain more detailed information on the elemental and phase compositions in a Pd/Mg–Ni film by means of analyzing Pd 3d5/2, Pd 3p3/2, Ni 2p3/2, Mg 1s and O 1s photoelectron spectra. The method was applied to analyze a typical Pd/Mg–Ni film sample. Results verified
that Pd can diffuse into the alloy layer. An Mg–O phase is formed near the surface. An Mg–Ni alloy phase dominates at deeper
regions. The Mg–Ni phase contains 80% of the total number of atoms in the film, and is non-stoichiometric and highly disordered.
Nevertheless, it can give a remarkable change of electrical resistivity during hydridation–dehydridation processes.
PACS 79.60.-i; 61.05.C-; 79.60.Ht 相似文献
20.
We propose the principle of operation of an optical near-field microscope on the basis of linear steady-state optical dimensional resonances in the system atom-probe–atoms of the sample. It is shown that such a microscope has high sensitivity and a spatial resolution of less than 1 nm and does not set limits on the choice of samples. The distribution of the optical fields in the wave and near zones in the near-field microscope at frequencies close to the optical dimensional resonances arising as a result of dipole-dipole interactions of atoms at small distances has been investigated. The optical scheme of the monatomic near-field microscope is presented. 相似文献