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V. V. Slavin

Publications and source records attributed to V. V. Slavin.

7 recordsLinked to original sources
arXiv2025

Peculiarities of optical absorption spectra of NdFe$_3$(BO$_3$)$_4$ crystal in magnetically ordered state and at the transition to spiral magnetic phase

We study experimentally and theoretically optical absorption spectra of neodymium ferroborate in the temperature range $6-32$ K. We show that the temperature dependences of integral intensities of absorption lines demonstrate qualitatively different behavior for $\sigma$- and $\pi$-polarizations of the light. We suggest that this behavior may be caused by the appearance of a spiral magnetic structure in the compound under study. To describe the temperature dependences of lines intensities we propose a theoretical model which takes into account the Dzyaloshinskii-Moriya interaction between Nd$^{3+}$ and Fe$^{3+}$ ions.

cond-mat.str-el↗
arXiv2025

Magnetic properties of the frustrated decorated Ising chain

Using the Kramers-Wannier transfer matrix method we studied several decorated Ising chains. The exact expressions for thermodynamic characteristics, including the ground state characteristics, were obtained. We considered a number of modeling chains with different signs and absolute values of exchange constants for the nearest- and the next-nearest neighbors. For these models we calculated the magnetization curves. The critical values of magnetic fields and corresponding magnetization plateau parameters were obtained. Analytic expressions for the ground state entropy were obtained for the chains with different interaction constants. The dependencies of the number of states with minimum energy (the degeneration of the ground state) as the function of the number of particles were found. It was shown that these dependencies are expressed in terms of well-known numerical sequences - Lucas numbers and Pell numbers, which, in the limit of a large number of particles, are proportional to the powers of the golden and silver sections. Therefore, the ground state entropy (per particle) of the systems under consideration can be described in terms of these sections and, therefore, is nonzero.

quant-ph↗
arXiv2024

Giant caloric effects in spin chain materials

The giant electro- and elasto-caloric effects in spin chain materials are predicted. The theory is based on the exact quantum mechanical solution of the problem. It is shown that the giant jumps in the entropy and the temperature caused by the caloric effect are weakly affected by the initial temperature. The effect can be used for the cooling of new quantum devices (like systems of qubits in quantum computers). On the other hand, since large changes are predicted in the narrow neighborhood of the critical point, the predicted effect can be used in ultra-sensitive electric and stress sensors for modern microelectronics.

quant-ph↗
arXiv2020

Accumulation of spin-polarized states of charge carriers and a spintronic battery

Spin valves based on materials in which the spin-flip is suppressed by the spatial separation of charge carriers, while maintaining electric neutrality in the valve volume, are considered. The possibility of using these valves as electric batteries is discussed. It is shown that if the potential difference across the valve is controlled, incommensurability effects such as the "devil's staircase" may be expected, which are associated with the Coulomb interaction and redistribution of electrons occurring while the battery is charged and discharged. The effects of the emergence and vanishing of spontaneous spin polarization of conduction electrons with a change in the Fermi level in the valve are predicted. Such spin valves can also be used in implementing spintronic memory cells, supercapacitors, and similar devices.

cond-mat.mes-hall↗
arXiv2013

The ground state structure of electron's ensemble on one-dimension disordered lattice

The ground state of interacting particles on a disordered one-dimensional host-lattice is studied by a direct numerical method. It is shown that if the concentration of particles is small, then even a weak disorder of the host-lattice breaks the long-range order of Generalized Wigner Crystal, replacing it by the sequence of blocks (domains) of particles with random lengths. The mean domains length as a function of the host-lattice disorder parameter is also found. It is shown that the domain structure can be detected by a weak random field, whose form is similar to that of the ground state but has fluctuating domain walls positions. This is because the generalized magnetization corresponding to the field has a sufficiently sharp peak as a function of the amplitude of fluctuations for small amplitudes.

cond-mat.dis-nn↗
arXiv1999

The Ground State of the ``Frozen'' Electron Phase in Two-Dimensional Narrow-Band Conductors with a Long-Range Interelectron Repulsion. Stripe Formation and Effective Lowering of Dimension

In narrow-band conductors a weakly screened Coulomb interelectron repulsion can supress narrow-band electrons' hopping, resulting in formation of a ``frozen'' electron phase which differs principally from any known macroscopic self-localized electron state including the Wigner crystal. In a zero-bandwidth limit the ``frozen'' electron phase is a classical lattice system with a long-range interparticle repulsion. The ground state of such systems has been considered in the case of two dimensions for an isotropic pair potential of the mutual particle repulsion. It has been shown that particle ordering into stripes and effective lowering of dimension universally resides in the ground state for any physically reasonable pair potential and for any geometry of the conductor lattice. On the basis of this fact a rigorous general procedure to fully describe the ground state has been formulated. Arguments have been adduced that charge ordering in High-T_c superconductors testifies to presence of a ``frozen'' electron phase in these systems.

cond-mat.str-el↗