arXiv subjects

P. O. Kazinski

Publications and source records attributed to P. O. Kazinski.

At least 19 recordsLinked to original sources

arXiv2026

Plasmon-polaritons in a rarefied nonrelativistic neutron gas

The electromagnetic properties of a dilute unpolarized nonrelativistic neutron gas are described in the case when neutron-by-neutron scattering is negligible. The Gaussian (Maxwell-Boltzmann) and Fermi-Dirac one-particle density matrices for the neutron gas are considered, the typical space scale of variations of these density matrices being assumed to be much larger than the the typical space scale of variations of the electromagnetic field. The Green functions for the static effective Maxwell equations are obtained. The parameters of a nonequilibrium neutron gas are found where this gas possesses a ferromagnetic instability. The analog of Friedel oscillations is described. The properties of plasmon-polaritons in the neutron gas are revealed. It turns out that the dispersion law of longitudinal and transverse plasmon-polaritons has an infinite number of branches at a given momentum. The region of parameters where the plasmon-polaritons can be regarded as quasiparticles is found. The plasmon-polaritons on a Gaussian wave packet of a single electron are described. Their dispersion law proves to have an infinite number of branches at a given momentum. It is shown that there exist stable longitudinal plasmon-polaritons even on a single electron.

physics.plasm-ph↗

arXiv2026

Coherent elastic scattering of low energy photons by neutrons

The Compton process with the initial states of photons and neutrons described by the density matrices of a general form is studied for low energies of photons. The coherent contribution to the inclusive probability to record a photon is investigated in detail. This contribution gives the hologram of the neutron one-particle density matrix. The evolution of the Stokes parameters of scattered photons is described. The susceptibility tensor of a neutron gas and a wave packet of a single neutron is obtained. The explicit expression for the photon polarization operator in the presence of free neutrons is derived. It turns out that this polarization operator possesses pole singularities in the short wavelength approximation. These singularities corresponding to the additional degrees of freedom are identified with plasmons and the respective plasmon-polaritons are described. There are eight independent plasmon-polariton modes in a neutron gas and on a single neutron wave packet. Some plasmon-polariton modes prove to be tachyonic and unstable manifesting a spontaneous generation of the magnetic field. The estimates of the parameters of the neutron gas when it becomes ferromagnetic are found. In the infrared limit, the neutron wave packet behaves in coherent Compton scattering as a point particle with dynamical magnetic moment, the additional degrees of freedom being reduced to the dynamical part of the magnetic moment.

hep-ph↗

arXiv2026

High-energy photon hologram of a photon gas

The photon hologram of a one-particle density matrix of a photon gas is derived including the case where the energy of a probe photon is above the electron-positron pair creation threshold. The explicit expressions for the holograms of a photon gas with one-particle density matrix in the form of a single Gaussian and of coherent and incoherent lattices of Gaussians are obtained. The conditions for resonant cones of coherent scattering by coherent and incoherent lattices are found. These conditions turn out to be different. The explicit expression for the dielectric susceptibility tensor of a photon gas and of a single photon prepared in arbitrary quantum states are derived on the probe photon mass-shell. It is established that a photon gas and a single photon behave in coherent photon scattering as a medium with linear and circular birefringence. This medium is transparent below the electron-positron creation threshold and is absorbing otherwise. In the high-energy limit, $\sqrt{s}\gg 2m$, it has the dielectric susceptibility tensor of a birefringent plasma except for a slow logarithmic scaling. It is shown that, for the probe photon energies of order $1$ GeV and higher, the energies of target photons of order $1$ eV and higher, and the photon gas density such that the classical intensity parameter is of order unity, the hologram of the photon gas can be measured with existing experimental facilities.

hep-th↗

arXiv2026

Transition radiation in helical metamaterials with strong spatial dispersion

The theory of transition radiation in helical metamaterials with strong spatial dispersion is developed in the framework of an effective field theory approach. The average number of photons radiated by a charged particle passing through a plate made of this metamaterial is obtained. Given the positions of the transition radiation maxima in momentum space for different velocities of a charged particle, the method for reconstruction of the dispersion law of plasmon-polaritons in metamaterials is proposed. Applying this method conversely, one can predict the radiation spectrum and polarization properties of transition radiation by means of the dispersion law of plasmon-polaritons in the metamaterial known, for example, from the effective model. It is shown that the strong spatial dispersion alters qualitatively the properties of transition radiation from a charged particle traversing normally a plate made of the helical metamaterial along its symmetry axis in the paraxial regime, viz., there is a nonzero forward radiation in contrast to transition radiation in media without strong spatial dispersion. Vavilov-Cherenkov radiation and the anomalous Doppler effect in helical metamaterials with strong spatial dispersion are described.

cond-mat.mes-hall↗

arXiv2026

Three-frequency helical undulator as a source of photons in composite twisted states

The properties of radiation from a three-frequency helical undulator are thoroughly investigated. It is shown that such undulators can be employed for generating photons in the so-called composite twisted states -- the states that are linear superpositions of modes with definite projections of the total angular momentum, amplitudes, relative phases, and polarizations. We find the explicit expressions and the selection rules for these parameters and establish that they can be governed in a predictable way by adjusting the parameters of the multifrequency helical undulator. In particular, the phases of three arbitrary modes admissible by selection rules in the composite state with definite energy can be made arbitrary by tuning the phases of one-frequency undulators comprising the three-frequency one. By solving Diophantine equations, we obtain simple expressions for the complex amplitude of coherent state of photons emitted by a three-frequency helical undulator and for the average number of radiated twisted photons in the case when the ratios of frequencies of the three-frequency undulator are rational numbers. The development of resonances and the control of composite states of radiated photons are studied numerically confirming the theoretical conclusions.

physics.acc-ph↗

arXiv2026

Radiation of twisted photons in elliptical multifrequency undulators

The theory of radiation of twisted photons in elliptical multifrequency undulators is developed. It is shown that helical multifrequency undulators can be employed as a bright and versatile source of photons in the states that are superpositions of the modes with definite projection of total angular momentum (TAM), amplitude, and relative phase. All these parameters of the state are readily controlled by the undulator design. The explicit expression for the amplitude of radiation of a twisted photon from a charged particle in the multifrequency undulator is derived. The energy spectrum of radiation and the selection rules for the TAM projection of radiated photons are described. The symmetry properties of the spectrum with respect to the TAM projection are established. The interpretation to the energy spectrum and to the selection rules is given in terms of virtual photons mediating between the charged particle and the undulator. The results obtained are also applicable to radiation of twisted photons produced by ultrarelativistic charged particles moving in plane multifrequency electromagnetic waves.

physics.acc-ph↗

arXiv2025

Detection of twisted radiowaves with Rydberg atoms

The dynamics of the outer electron in an alkali atom in the presence of structured electromagnetic waves is described. The interaction of the alkali Rydberg atom with twisted radiowaves is considered. The two schemes for Rydberg-atom based detector of twisted radiowaves are proposed. According to the theoretical model for these detectors, they can record a source of twisted radiowaves with power down to several nW. The first scheme of the detector employs the nondipole transitions between Rydberg states induced by twisted radio photons. The second scheme involves the array of Rydberg-atom based antennas, every antenna measuring the dipole transitions excited by plane radiowaves comprising the twisted one.

physics.atom-ph↗

arXiv2025

Observation of transition radiation carrying orbital angular momentum

Twisted photons carrying orbital angular momentum, which have potential applications spanning diverse fields, have been extensively studied since the theoretical work of Allen \textit{et al}. in 1992. Various methods for direct producing twisted photons have been explored, leveraging the rotational (spiral) motion of relativistic electrons in phenomena such as undulator radiation. In the present study, transition radiation carrying orbital angular momentum is observed for the first time. This radiation was generated by 220 MeV electrons incident on an Au-coated Si wafer. The orbital angular momentum was measured by analyzing the diffraction patterns produced as the radiation passed through a triangular aperture and a double slit. These results demonstrate that twisted photons can also be generated through the interaction of rectilinearly moving electrons with a solid target.

physics.acc-ph↗

arXiv2024

Plasmon-polaritons on a single electron

The explicit expression for the photon polarization operator in the presence of a single electron is found in the $in$-$in$ formalism in the one-loop approximation out of the photon mass-shell. This polarization operator describes the dielectric permittivity of a single electron wave packet in coherent scattering processes. The plasmons and plasmon-polaritons supported by a single electron wave packet are described. The two limiting cases are considered: the wavelength of the external electromagnetic field is much smaller than the typical scale of variations of the electron wave packet and the wavelength of the external electromagnetic field is much larger than the size of the electron wave packet. In the former case, there are eight independent plasmon-polariton modes. In the latter case, the plasmons boil down to the dynamical dipole moment attached to a point electron. Thus, in the infrared limit, the electron possesses a dynamical electric dipole moment manifesting itself in coherent scattering processes.

hep-ph↗

arXiv2024

Surface photoelectric effect by twisted photons as a source of twisted electrons

The theory of surface photoelectric effect by twisted photons is developed. The explicit expression for the probability to record a twisted photoelectron is derived. The conditions when the surface photoelectric effect can be used as a pure source of twisted electrons are found. It is shown that the lightly doped n-InSb crystal with interface without defects at temperatures lower than $2.5$ K satisfies these conditions. The Dirac and Weyl semimetals with electron chemical potential near the top of the Dirac cone obey these conditions at temperatures lower than $60$ K and can also be employed for design of pure sources of twisted electrons by the photoelectric effect.

cond-mat.mes-hall↗

arXiv2024

Radiation from Dirac fermions caused by a projective measurement

The theory of radiation of photons from Dirac particles caused by a projective measurement is developed. The explicit expressions for the inclusive probability to record a chain of events that the Dirac fermion had been measured in a certain state and after that the photon was recorded are derived. Stimulated and spontaneous radiations are considered. It is shown that in both cases the properties of radiation due to measurement resembles the properties of edge or transition radiation. In the case of stimulated radiation from a single particle, its wave function creates photons coherently as a charged fluid, i.e., the amplitudes of radiation from the points of the particle wave packet are summed. In the case of spontaneous radiation, the radiation of photons is incoherent, i.e., the probabilities of radiation from the points of the particle wave packet are added up. It is shown that stimulated radiation due to measurement can be used to trace the dynamics and collapse of the wave function of the Dirac particle. A systematic procedure taking into account a finiteness of the measurement time is presented. It is established that radiation due to measurement can be used as a source of hard photons, but the finiteness of the measurement time imposes an upper bound on the energy of radiated photons: the measurement time must be smaller than the radiation formation time, the latter being in inverse proportion to the photon energy. In the ultrarelativistic limit, the radiation formation time can be rather large. Several examples of radiation due to measurement of the state of free Dirac particles are investigated in detail. Namely, we scrutinize the radiation due to measurement of the spin projection, of the momentum, and of the coordinate for a general initial state of Dirac particles. The particular cases of uncorrelated and entangled particles in the beam are considered.

quant-ph↗

arXiv2024

Exploring spatial dispersion in helical wired media: An effective field theory approach

The propagation of electromagnetic waves in helical media with spatial dispersion is investigated. The general form of the permittivity tensor with spatial dispersion obeying the helical symmetry is derived. Its particular form describing the medium made of conducting spiral wires with pitch $2π/|q|$ is studied in detail. The solution of the corresponding Maxwell equations is obtained in the paraxial limit. The dispersion law of the electromagnetic field modes, their polarization, and the integral curves of the Poynting vector are analyzed. The dispersion law of photons in such a medium possesses polarization dependent forbidden bands. The widths of these gaps and their positions are tunable in a wide range of energies. If the helix angle $α$ is not close to $π/2$ and the plasma frequency $ω_p\ll|q|$, then there are two chiral forbidden bands. The energies of one chiral forbidden band are near the plasma frequency $ω_p$ and the width of this gap is of order $|q|$. The other chiral forbidden band is narrow and is located near the photon energy $|q|$. In the case $α\approxπ/2$, the first chiral forbidden band becomes a total forbidden band. If, additionally, the plasma frequency $ω_p\gg|q|$, then the second forbidden band turns into a wide polarization dependent forbidden band. For the energies belonging to this interval the photons with only one linear polarization are transmitted through the medium and the polarization plane of transmitted photons is rotated. In the nonparaxial regime, the solution of the Maxwell equations is obtained in the shortwave approximation. The dispersion law of the electromagnetic field modes, their polarization, and the integral curves of the Poynting vector are found. Scattering of the electromagnetic waves by a slab made of the helical wired medium is considered.

cond-mat.mes-hall↗

arXiv2024

Excitation of multipolar transitions in nuclei by twisted photons

The explicit expression for the probability of absorption of a twisted photon by an atomic nucleus has been obtained. It is shown that photoabsorption obeys the selection rule $j\geqslant|m_γ|$, where $j$ is the multipolarity of the nuclear transition, when the nuclei lie near the axis along which a twisted photon with a projection of the total angular momentum $m_γ$ propagates. In the long-wave limit, the main contribution to the probability of absorption of a twisted photon comes from the multipole transition with $j=|m_γ|$. The absorption coefficient for twisted photons in a target consisting of many nuclei has been found.

nucl-th↗

arXiv2023

Inclusive probability to record an electron in elastic electromagnetic scattering by a spin one-half hadron wave packet

The inclusive probability to record an electron in elastic electromagnetic scattering of an electron by a spin one-half hadron is obtained, the initial quantum states of the electron and the hadron being described by the density matrices of a general form. Contrary to the Rosenbluth formula for the differential cross-section for this process, the first nontrivial contribution to the inclusive probability turns out to be of order $α$ and not $α^2$. This contribution describes the interference between the trivial contribution to the $S$-matrix and the leading contribution to its connected part. The explicit expression for this interference terms is derived. For example, for Gaussian wave packets the interference contribution to the inclusive probability is of relative order $2\times 10^{-2}$ in comparison with the contribution of the free passed particle for the nonrelativistic proton and the $10$ MeV electron with the normal deviation of momenta in the electron and hadron wave packets of order $10$ keV. It is shown that the same interference term arises when the electron is scattered by the classical electromagnetic field produced by the hadron electromagnetic current averaged with respect to the free evolving density matrix of the hadron, even in the case of a single hadron. The interference term describes coherent scattering of the electron by the hadron wave packet and is immune to the quantum recoil experienced by a hadron due to scattering. The effective electron mass operator is found on the mass-shell.

hep-ph↗

arXiv2023

Multiplexing signals with twisted photons by a circular arc phased array

The theory of multiplexing electromagnetic signals by means of twisted photons generated by a uniform circular array (UCA) is developed in the case when the receiving antenna represents an array of elements located on a circular arc. The radiating elements are characterized by certain current distributions and are not points, in general. The polarization of created electromagnetic waves is fully taken into account. The notion of discrete twisted photons of the order $N$ is introduced and orthogonality of these modes modulo $N$ is established. Both paraxial and planar discrete twisted photons are considered. The explicit expressions for the signals received are obtained. It is shown that, in the simplest scenario, a $K$ times decrease of the circular arc where the receiving array antenna is placed results in a $K$ times decrease of the number of independent information channels. In the more sophisticated approach, one can restore all $N\gg1$ independent information channels in receiving the signal by an array antenna with $N$ elements located on a circular arc with the central angle $2π/K$. However, this problem becomes rapidly ill-conditioned as one increases $K$. The method mitigating this issue is described. The estimates for the corresponding condition numbers are found. The scenario with beam steering, where the radiation produced by the UCA is concentrated near the receiving circular arc array antenna, is also investigated. The orthogonality of the information channels is proved in this case and the corresponding transformation matrix and its condition number are found.

physics.app-ph↗

arXiv2023

Multichannel scattering for the Schrödinger equation on a line with different thresholds at both infinities

The multichannel scattering problem for the stationary Schrödinger equation on a line with different thresholds at both infinities is investigated. The analytical structure of the Jost solutions and of the transition matrix relating the Jost solutions as functions of the spectral parameter is described. Unitarity of the scattering matrix is proved in the general case when some of the scattering channels can be closed and the thresholds can be different at left and right infinities on the line. The symmetry relations of the $S$-matrix are established. The condition determining the bound states is obtained. The asymptotics of the Jost functions and of the transition matrix are derived for a large spectral parameter.

math-ph↗

arXiv2023

Susceptibility of a single photon wave packet

The explicit compact expression for the susceptibility tensor of a single photon wave packet on the photon mass-shell is derived. It is assumed that the probe photon is hard, the test photon is soft, and their total energy is below the electron-positron pair creation threshold. It turns out that a single photon wave packet can be regarded as a birefringent gyrotropic dispersive medium in the process of light-by-light scattering. The explicit expression for the inclusive probability to record the probe photon in the process of light-by-light scattering is obtained in the first nontrivial order of perturbation theory where the interference effect of the free passed and scattered parts of the photon wave function dominates. This effect is of order $α^2$ in contrast to the standard contribution to the light-by-light scattering cross-section which is of order $α^4$. The possible nontrivial shapes of the wave functions of probe and test photons are taken into account. The evolution of the Stokes parameters of a probe photon is described. The change of the Stokes parameters is rather large for hard probe photons and sufficiently intense beams of soft test photons.

hep-th↗

arXiv2022

Photoexcitation of planar Wannier excitons by twisted photons

Photoexcitation of planar Wannier excitons by twisted photons in thin semiconductor films is investigated. The explicit general formulas for transition probabilities between exciton states are derived. The selection rules for the projection of the total angular momentum are obtained. As examples, the Coulomb and Rytova-Keldysh electron-hole interaction potentials are considered. The use of planar excitons as a pure on-chip source of twisted photons is discussed. The formulas obtained also describe photoexcitation of states of electrons and holes bound to charged impurities in planar semiconductors.

cond-mat.mes-hall↗