arXiv subjects

M. D. Ivanovich

Publications and source records attributed to M. D. Ivanovich.

6 recordsLinked to original sources

arXiv2013

Properties of the outer crust of strongly magnetized neutron stars from Hartree-Fock-Bogoliubov atomic mass models

The equilibrium properties of the outer crust of cold nonaccreting magnetars (i.e. neutron stars endowed with very strong magnetic fields) are studied using the latest experimental atomic mass data complemented with a microscopic atomic mass model based on the Hartree-Fock-Bogoliubov method. The Landau quantization of electron motion caused by the strong magnetic field is found to have a significant impact on the composition and the equation of state of crustal matter. It is also shown that the outer crust of magnetars could be much more massive than that of ordinary neutron stars.

astro-ph.HE↗

arXiv2013

Unified description of dense matter in neutron stars and magnetars

We have recently developed a set of equations of state based on the nuclear energy density functional theory providing a unified description of the different regions constituting the interior of neutron stars and magnetars. The nuclear functionals, which were constructed from generalized Skyrme effective nucleon-nucleon interactions, yield not only an excellent fit to essentially all experimental atomic mass data but were also constrained to reproduce the neutron-matter equation of state as obtained from realistic many-body calculations.

astro-ph.HE↗

arXiv2012

Equation of state of magnetar crusts from Hartree-Fock-Bogoliubov atomic mass models

The equation of state (EoS) of the outer crust of a cold non-accreting magnetar has been determined using the model of Lai and Shapiro (1991). For this purpose, we have made use of the latest experimental atomic mass data complemented with a Hartree-Fock-Bogoliubov (HFB) mass model. Magnetar crusts are found to be significantly different from the crusts of ordinary neutron stars.

astro-ph.HE↗

arXiv2006

Variational band theory of vibronic polarons in crystals. III. Numerical calculations

In the preceding Part II, we derived variational equations for the phonon Fourier amplitudes and for the Fourier amplitudes of the fractional contribution of the electronic bands to the trial variational state. These equations are now solved by means of iterations for each value of the total momentum in order to obtain the energy vs. momentum relation for the ground state. Another result is mapping out the phonon and band Fourier amplitudes in the parameter space of the mixing constant and the electron hopping energy.

cond-mat.supr-con↗

arXiv2005

The O-M-O triatomic molecule: Basic unit of cuprates & manganates

The O(oxygen)-M(metal)-O(oxygen) molecule is a basic unit of high-temperature superconducting cuprates and colossal magnetoresistance exhibiting manganates. This molecule can be regarded either as an element of a linear chain or as an ingredient of the corresponding cuprate or manganate lattice. The symmetry of the unit being different in the two approaches, group theory imposes different limitations on conceivable vibrational modes and atomic otbitals that control its transport and optical properties. We now calculate the electron hopping energies along Cu(P0-O(A) bonds, sites for nonlocal electron-vibrational mode coupling. We find the electric transport along the O(A)-Cu(P)-O(A) molecule dominated by scattering from bond polarons which is reflected in the two-branch character of the temperature dependence of its electric resistance.

cond-mat.supr-con↗

arXiv2005

Itinerant vibronic polarons: A Merrifield approach I. Low energy range calculations

We extend Merrifield's Variational Ansatz in the variational band theory of polarons to cover a frame of two electronic bands mixed by an Einstein phonon. The Hamiltonian is composed of the local and hopping energy terms, the vibrational energy, and a band-mixing term linear in the electron-phonon coupling. The eigenstate is a linear combination of Merrifield states in either electron band. The variational equations are solved numerically, so as to obtain the energy vs. momentum relation in ground state. Our variational method generates either Jahn-Teller polarons if the electronic bands degenerate or Pseudo-Jahn-Teller polarons if they nearly degenerate, both entities regarded as likely carriers in metal-oxide manifolds of high-Tc superconducting cuprates and colossal magnetoresistance exhibiting manganates.

cond-mat.supr-con↗