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We show that spontaneous breaking of the translational symmetry (SBTS) of strongly interacting electron and phonon fields acknowledged in lightly doped cuprates to interpret broad bands in their ARPES and optical conductivity spectra influences the carrier distribution function as charge carrier momentum is no longer certain. We develop appropriate distribution and use it to calculate the carrier concentration in different states in essentially doped systems with SBTS. This allows studying doping and temperature evolution of ARPES spectra of such systems. We reveal that at increasing both temperature or doping polarons concede dominance to bipolarons that results in a shift of the broad band maximum to higher binding energy as it occurs in ARPES spectra of cuprates. At further doping delocalized carriers appear and coexist with bipolarons. We show that intimate property of systems with SBTS is partition of the momentum space between autolocalized and delocalized carriers caused by Pauli exclusion rule. We demonstrate that in ARPES spectra such partition manifests itself as `vertical dispersion` or waterfalls universally observed in all the cuprates at essential doping and in undoped parent compounds. Thus, studying the carriers distribution in systems where electron-phonon interaction breaks the translation symmetry leads simultaneously to both types of waterfalls observed in significantly doped and undoped cuprates. The article also represents the methods developed to calculate the band in ARPES spectrum caused by bipolaron photodissociation and the bipolaron binding energy and radius using coherent states for the phonon field characterization., Comment: 18 pages, 6 figures

The phenomenon is described that is an analogue of the Vavilov-Cherenkov phenomenon and that could be observable in a space with the boundary separated a well reflecting light metal and a dielectric. An electron that is moving at a constant velocity in proximity to the such boundary creates surface plasmon-polaritons with a phase velocity that is below the electron velocity. The linear momentum of a photon in the created plasmon-polariton is calculated. This momentum could be as high as a doubled initial electron momentum. In the other case the electron that has created the photon in the plasmon-polariton could totally lost its velocity. It is shown that at the non-zero temperature this process has a non-zero probability.

On purpose to establish the differences in probabilities of spontaneous radiative emission of an atom in a free space and in a nonuniform space with a nanospheroid the field strength E and the density of states rho_E of the mode n_10 of a free space and of the TM_0 nanocylinder mode are defined. A nanocylinder is an approximate model of a nanospheroid. The probability of a spontaneous transition is proportional to E^2*rho_E in the both cases. It is found that the emission probability to the nanospheroid mode is hundreds times and more higher than the spontaneous emission probability in the free space., Comment: 7 pages, 3 figures

An effect that is an analogue to the Vavilov-Cherenkov effect in a uniform space would be observed in a space with a boundary of well reflecting light metal-dielectric. The main difference is in that quanta of some electron volt would be excited by an electron of energy of some tens of electron volts. This would become possible because the surface plasmon velocity is very small as compared with the velocity of waves of a uniform space. Beetwen excited plasmons there is a plasmon with a linear momentum as high as the doubled initial momentum of the electron., Comment: 4 pages, 2 figures

This paper contains details of calculation of the surface wave excitation by a fast moving charged particle in a thin uniform metal film surrounded by a dielectic medium. Early on the effect was described in the paper arXiv:0911.0565 03 November 2009. It is shown that the Vavilov-Cherenkov like effect for the surface waves could arise for particles whose velocities are ten- and even hundred-times lower than the corresponding velocities in a uniform medium.

The theory is presented of surface wave excitation by a fast moving charged particle in a thin uniform metal film surrounded by a dielectric medium. It is shown that the Vavilov-Cherenkov like effect for the sufface waves could arise for particles whose velocities are ten- and even hundred-times lower than the corresponding velocities in a uniform medium., Comment: 10 pages, 7 figures

The paper contains a theory of laser action in a so called SPASER, a laser with a surface plasmon. The goal of the theory development is an ascertainment of physical nature of SPASER lasers that were successfully put into action by M. A. Noginov et al, announced in the paper entitled Demonstration of a spaser-based nanolaser, and by Xiang Zhang et al, the paper Plasmon lasers at deep subwavelength scale, both papers in Nature Advance online publication, August 2009. Plasmonic modes have huge losses but simultaneously the probabilities of radiative processes in atoms (molecules) with emission of radiation into such modes are increased thousandfold as compared with probabilities to radiate in free space. This makes clear how the losses are compensated by amplification. It is made apparent the kinship of physical nature of the phenomenon with that of of the SERS., Comment: 5 pages

The Vavilov-Cerenkov phenomenon - light emission during the motion of a fast electron in a dense medium is observable in homogeneous media as well as in inhomogeneous media like photonic crystals. So long as a space (homogeneous or inhomogeneous) contains natural waves with phase velocities that are lower than the velocity of a flying through electron then a Cerenkov emission of light would appear. In nanofilms and nanowires made of silver, gold, copper there are so called surface plasmon polaritons, namely natural waves with a low phase velocity. These waves velocity could be by tens and hundreds times lower than the light velocity in vacuum. An electron with a velocity that is comparatively lower than a velocity of an electron that is able to emit in a uniform medium could emit Cerenkov light. Dispersion relations are calculated for the corresponding plasmons as well as the angles of emission of the plasmons of corresponding frequencies., Comment: 5 pages, 4 figures

The paper is of a methodological character and has as a goal to give a brief description of the concept of theory and practical application of very slow optical plasmons. They exist on the metal-dielectric boundaries, namely, on very thin metal films and fibers and as standing waves on metal spheres and ellipsoids. The material presented in the paper features by widening the common concepts of electromagnetic modes of various spaces, of the probability of spontaneous emission, of creation of optical images, of the limits of optical focusing, and of the photon linear momentum. All mentioned studies are completed in recent years. The problem of the photon momentum in a dielectric medium was the topic of irreconcilable disputes for 100 years starting in the time of appearing of Minkowski and Abraham famous papers. Various practical applications are surveyed: the experiments with a great intensification of an atom spontaneous emission into a plasmonic field mode of a metal nanoparticle, the experiments on focusing optical radiation into a spot that substantially smaller than a diffraction limited spot, a so called near perfect Pendry lens that produces the image with details that substantially smaller than defined by diffraction, and lastly, the concept of hundredfold and more magnification of a photon mechanical linear momentum in a plasmon. The work completed is supported by RFBR, grants Nos 05-02-19647, 07-02-01328., Comment: 19 pages, 13 figures

A momentum of the photon in a surface plasmon could be hundreds and even thousand times higher as compared to a momentum of a photon in a free space. Such a photon could be scattered on an electron the later being supplied by a notable momentum. This momentum is approximately of the same value as a momentum transposed by an X-ray photon. A physical fundamental importance of the observation is outlined. Various practical applications of the phenomenon are proposed including an optical nanodevice., Comment: 3 pages

Surface optical plasmons on metal-dielectric boundaries of various shapes are studied. The study features by the exploration of plasmons of the frequency that is larger than $\omega_{pl}/\sqrt{2}$ and approximately equal to $\omega _{pl}$. These plasmons exist on thin films, thin cylinders, and on spheres. Such a plasmon does not exist on a single surface. For applications the use of plasmons of the ~$\omega_{pl}$ frequency means the promotion of nanophotonics devices into a short wavelength range. For Ag this means the promotion to the wavelength of 140 nm., Comment: 5 pages, 4 figures

Two devices for subwave length focusing of light are explored. The first one is a thin film of a well reflecting metal which the converging beam of surface plasmons with a wave number $h>>\omega_0/c$ is excited on. The waist of this beam has a cross section that is much smaller than $\lambda_0^2$. The second device is a linear nanoantenna with a gap in the middle. A resonance plasmon is excited in the antenna. The field in the gap concentrates on the spot that is much smaller than $\lambda_0^2$. In both cases the effect of field enhancement in the spot of subwave length focusing is greatly decreased because of propagation losses in the first case and because of a small excitation cross section in the second case. It is suggested to improve on the effect of excitation of the film and the nanoantenna by means of interaction with an adjacent atom or quantum dot., Comment: 7 pages, 8 figures

The field of an evanescent wave in a space with a thin metal layer is explored. The wave number of the evanescent wave exceeds many times the wave number of a uniform plane wave in adjoining gaps. In agreement with the results of the Pendry's paper of the 2000 year the field behind the metal layer occurs to be amplified as compared to the field in absence of the metal layer. Pendry has demonstrated the effect for the metal of the dielectric constant of -1. In this paper it is shown that the effect exists for the dielectric constant of -15 and for an arbitrary thickness of the adjoining gaps. This widens the number of possible applications. The metal losses do not destoy the effect appreciably., Comment: 8 pages, 7 figures