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Pavel A Andreev - One of the best experts on this subject based on the ideXlab platform.
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Dielectric Permeability tensor and linear waves in spin 1 2 quantum kinetics with non trivial equilibrium spin distribution functions
Physics of Plasmas, 2017Co-Authors: Pavel A Andreev, L S KuzmenkovAbstract:A consideration of waves propagating parallel to the external magnetic field is presented. The Dielectric Permeability tensor is derived from the quantum kinetic equations with non-trivial equilibrium spin-distribution functions in the linear approximation on the amplitude of wave perturbations. It is possible to consider the equilibrium spin-distribution functions with nonzero z-projection proportional to the difference of the Fermi steps of electrons with the chosen spin direction, while x- and y-projections are equal to zero. It is called the trivial equilibrium spin-distribution functions. In the general case, x- and y-projections of the spin-distribution functions are nonzero which is called the non-trivial regime. A corresponding equilibrium solution is found in Andreev [Phys. Plasmas 23, 062103 (2016)]. The contribution of the nontrivial part of the spin-distribution function appears in the Dielectric Permeability tensor in the additive form. It is explicitly found here. A corresponding modificatio...
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Dielectric Permeability tensor and linear waves in spin 1 2 quantum kinetics with non trivial equilibrium spin distribution functions
arXiv: Plasma Physics, 2017Co-Authors: Pavel A Andreev, L S KuzmenkovAbstract:A consideration of waves propagating parallel to the external magnetic field is presented. The Dielectric Permeability tensor is derived from quantum kinetic equations with non-trivial equilibrium spin-distribution functions (NTESDF) in the linear approximation on amplitude of wave perturbations. In general case, x- and y-projections of the SDF are nonzero which is called the non-trivial regime. Corresponding equilibrium solution is found. Contribution of the NTESDF appears in the Dielectric Permeability tensor in the additive form. It is explicitly found here. Corresponding modification in the dispersion equation for the transverse waves is derived. Contribution of NTESDF in the spectrum of transverse waves is calculated numerically. It is found that the term caused by the NTESDF can be comparable with the classic terms for the relatively small wave vectors and frequencies above the cyclotron frequency. In majority of regimes, the extra spin caused term dominates over the spin term found earlier, except the small frequency regime, where their contributions in the whistler spectrum are comparable. A decrease of the left-hand circularly polarized wave frequency, an increase of the high-frequency right-hand circularly polarized wave frequency, and a decrease of frequency changing by an increase of frequency at the growth of the wave vector for the whistler are found. A dramatic decrease of the spin wave frequency resulting in several times larger group velocity of the spin wave is found either. Found dispersion equations are used for obtaining of an effective quantum hydrodynamics reproducing these results. This generalization requires the introduction of corresponding equation of state for the thermal part of the spin current in the spin evolution equation.
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kinetic analysis of spin current contribution to spectrum of electromagnetic waves in spin 1 2 plasma i Dielectric Permeability tensor for magnetized plasmas
Physics of Plasmas, 2017Co-Authors: Pavel A AndreevAbstract:The Dielectric Permeability tensor for spin polarized plasmas is derived in terms of the spin-1/2 quantum kinetic model in six-dimensional phase space. Expressions for the distribution function and spin distribution function are derived in linear approximations on the path of Dielectric Permeability tensor derivation. The Dielectric Permeability tensor is derived for the spin-polarized degenerate electron gas. It is also discussed at the finite temperature regime, where the equilibrium distribution function is presented by the spin-polarized Fermi-Dirac distribution. Consideration of the spin-polarized equilibrium states opens possibilities for the kinetic modeling of the thermal spin current contribution in the plasma dynamics.
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kinetic analysis of spin current contribution to spectrum of electromagnetic waves in spin 1 2 plasma part i Dielectric Permeability tensor for magnetized plasmas
arXiv: Plasma Physics, 2016Co-Authors: Pavel A AndreevAbstract:The Dielectric Permeability tensor for spin polarized plasmas is derived in terms of the spin-1/2 quantum kinetic model in six-dimensional phase space. Expressions for the distribution function and spin distribution function are derived in linear approximations on the path of Dielectric Permeability tensor derivation. The Dielectric Permeability tensor is derived the spin-polarized degenerate electron gas. It is also discussed at the finite temperature regime, where the equilibrium distribution function is presented by the spin-polarized Fermi-Dirac distribution. Consideration of the spin-polarized equilibrium states opens possibilities for the kinetic modeling of the thermal spin current contribution in the plasma dynamics.
L S Kuzmenkov - One of the best experts on this subject based on the ideXlab platform.
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Dielectric Permeability tensor and linear waves in spin 1 2 quantum kinetics with non trivial equilibrium spin distribution functions
Physics of Plasmas, 2017Co-Authors: Pavel A Andreev, L S KuzmenkovAbstract:A consideration of waves propagating parallel to the external magnetic field is presented. The Dielectric Permeability tensor is derived from the quantum kinetic equations with non-trivial equilibrium spin-distribution functions in the linear approximation on the amplitude of wave perturbations. It is possible to consider the equilibrium spin-distribution functions with nonzero z-projection proportional to the difference of the Fermi steps of electrons with the chosen spin direction, while x- and y-projections are equal to zero. It is called the trivial equilibrium spin-distribution functions. In the general case, x- and y-projections of the spin-distribution functions are nonzero which is called the non-trivial regime. A corresponding equilibrium solution is found in Andreev [Phys. Plasmas 23, 062103 (2016)]. The contribution of the nontrivial part of the spin-distribution function appears in the Dielectric Permeability tensor in the additive form. It is explicitly found here. A corresponding modificatio...
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Dielectric Permeability tensor and linear waves in spin 1 2 quantum kinetics with non trivial equilibrium spin distribution functions
arXiv: Plasma Physics, 2017Co-Authors: Pavel A Andreev, L S KuzmenkovAbstract:A consideration of waves propagating parallel to the external magnetic field is presented. The Dielectric Permeability tensor is derived from quantum kinetic equations with non-trivial equilibrium spin-distribution functions (NTESDF) in the linear approximation on amplitude of wave perturbations. In general case, x- and y-projections of the SDF are nonzero which is called the non-trivial regime. Corresponding equilibrium solution is found. Contribution of the NTESDF appears in the Dielectric Permeability tensor in the additive form. It is explicitly found here. Corresponding modification in the dispersion equation for the transverse waves is derived. Contribution of NTESDF in the spectrum of transverse waves is calculated numerically. It is found that the term caused by the NTESDF can be comparable with the classic terms for the relatively small wave vectors and frequencies above the cyclotron frequency. In majority of regimes, the extra spin caused term dominates over the spin term found earlier, except the small frequency regime, where their contributions in the whistler spectrum are comparable. A decrease of the left-hand circularly polarized wave frequency, an increase of the high-frequency right-hand circularly polarized wave frequency, and a decrease of frequency changing by an increase of frequency at the growth of the wave vector for the whistler are found. A dramatic decrease of the spin wave frequency resulting in several times larger group velocity of the spin wave is found either. Found dispersion equations are used for obtaining of an effective quantum hydrodynamics reproducing these results. This generalization requires the introduction of corresponding equation of state for the thermal part of the spin current in the spin evolution equation.
A. A. Yushkanov - One of the best experts on this subject based on the ideXlab platform.
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Transverse electric conductivity and Dielectric Permeability in quantum non-degenerate and maxwellian collisional plasma with variable collision frequency in Mermin's approach
arXiv: Plasma Physics, 2013Co-Authors: A. V. Latyshev, A. A. YushkanovAbstract:Formulas for transverse conductance and Dielectric Permeability in quantum non-degenerate and Maxwellian collisional plasma with arbitrary variable collision frequency in Mermin's approach are deduced. Frequency of collisions of particles depends arbitrarily on a wave vector. The special case of frequency of collisions proportional to the module of a wave vector is considered. The graphic analysis of the real and imaginary parts of Dielectric function is made.
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Transverse electric conductivity and Dielectric Permeability in quantum degenerate collisional plasma with variable collision frequency in Mermin's approach
arXiv: Plasma Physics, 2013Co-Authors: A. V. Latyshev, A. A. YushkanovAbstract:Formulas for transverse conductance and Dielectric Permeability in quantum degenerate collisional plasma with arbitrary variable collision frequency in Mermin's approach are deduced. Frequency of collisions of particles depends arbitrarily on a wave vector. For this purpose the kinetic Shr\"{o}dinger - Boltzmann equation with collision integral of relaxation type in momentum space is applied. The case of degenerate Fermi plasma is allocated and investigated. The special case of frequency of collisions proportional to the module of a wave vector is considered. The graphic analysis of the real and imaginary parts of Dielectric function is made.
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Longitudinal Dielectric Permeability into quantum degenerate plasma with frequency of collisions proportional to the module of a wave vector
arXiv: Plasma Physics, 2013Co-Authors: A. V. Latyshev, A. A. YushkanovAbstract:Formulas for the longitudinal Dielectric Permeability in quantum degenerate collisional plasma with the frequency of collisions proportional to the module of the wave vector, in Mermin's approach, are received. Equation of Shr\"{o}dinger - Boltzmann with integral of collisions relaxation type in Mermin's approach is applied. It is spent numerical and graphic comparison of the real and imaginary parts of Dielectric function of non-degenerate and maxwellian collisional quantum plasma with a constant and a variable frequencies of collisions. It is shown, that the longitudinal Dielectric function weakly depends on a wave vector.
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Longitudinal Dielectric Permeability into quantum non-degenerate and maxwellian plasma with frequency of collisions proportional to the module of a wave vector
arXiv: Plasma Physics, 2013Co-Authors: A. V. Latyshev, A. A. YushkanovAbstract:Formulas for the longitudinal Dielectric Permeability in quantum non-degenerate and maxwellian collisional plasma with the frequency of collisions proportional to the module of the wave vector, in Mermin's approach, are received. Equation of Shr\"{o}dinger - Boltzmann with integral of collisions relaxation type in Mermin's approach is applied. It is spent numerical and graphic comparison of the real and imaginary parts of Dielectric function of non-degenerate and maxwellian collisional quantum plasma with a constant and a variable frequencies of collisions. It is shown, that the longitudinal Dielectric function weakly depends on a wave vector.
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Longitudinal Permeability of collisional plasmas under arbitrary degree of degeneration of electron gas
arXiv: Mathematical Physics, 2010Co-Authors: A. V. Latyshev, A. A. YushkanovAbstract:Electric conductivity and Dielectric Permeability of the non-degenerate electronic gas for the collisional plasmas under arbitrary degree of degeneration of electron gas is found. The kinetic equation of Wigner - Vlasov - Boltzmann with collision integral in relaxation form BGK (Bhatnagar, Gross and Krook) in coordinate space is used. Dielectric Permeability with using of the relaxation equation in the momentum space has been received by Mermin. Comparison with Mermin's formula has been realized. It is shown, that in the limit when Planck's constant tends to zero expression for Dielectric Permeability passes in the classical.
A. V. Latyshev - One of the best experts on this subject based on the ideXlab platform.
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Longitudinal Dielectric Permeability of a quantum degenerate plasma with a constant collisional frequency
High Temperature, 2014Co-Authors: A. V. Latyshev, Alexander YushkanovAbstract:A formula for degenerate plasma has been derived from the general formula of the Dielectric Permeability of a quantum collisional plasma. The real and imaginary parts of the Dielectric Permeability of the quantum collisional degenerate plasma have been studied graphically, and they have been compared with the real and imaginary parts of the Dielectric Permeability of the collisional classic degenerate plasma.
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Transverse electric conductivity and Dielectric Permeability in quantum non-degenerate and maxwellian collisional plasma with variable collision frequency in Mermin's approach
arXiv: Plasma Physics, 2013Co-Authors: A. V. Latyshev, A. A. YushkanovAbstract:Formulas for transverse conductance and Dielectric Permeability in quantum non-degenerate and Maxwellian collisional plasma with arbitrary variable collision frequency in Mermin's approach are deduced. Frequency of collisions of particles depends arbitrarily on a wave vector. The special case of frequency of collisions proportional to the module of a wave vector is considered. The graphic analysis of the real and imaginary parts of Dielectric function is made.
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Transverse electric conductivity and Dielectric Permeability in quantum degenerate collisional plasma with variable collision frequency in Mermin's approach
arXiv: Plasma Physics, 2013Co-Authors: A. V. Latyshev, A. A. YushkanovAbstract:Formulas for transverse conductance and Dielectric Permeability in quantum degenerate collisional plasma with arbitrary variable collision frequency in Mermin's approach are deduced. Frequency of collisions of particles depends arbitrarily on a wave vector. For this purpose the kinetic Shr\"{o}dinger - Boltzmann equation with collision integral of relaxation type in momentum space is applied. The case of degenerate Fermi plasma is allocated and investigated. The special case of frequency of collisions proportional to the module of a wave vector is considered. The graphic analysis of the real and imaginary parts of Dielectric function is made.
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Longitudinal Dielectric Permeability into quantum degenerate plasma with frequency of collisions proportional to the module of a wave vector
arXiv: Plasma Physics, 2013Co-Authors: A. V. Latyshev, A. A. YushkanovAbstract:Formulas for the longitudinal Dielectric Permeability in quantum degenerate collisional plasma with the frequency of collisions proportional to the module of the wave vector, in Mermin's approach, are received. Equation of Shr\"{o}dinger - Boltzmann with integral of collisions relaxation type in Mermin's approach is applied. It is spent numerical and graphic comparison of the real and imaginary parts of Dielectric function of non-degenerate and maxwellian collisional quantum plasma with a constant and a variable frequencies of collisions. It is shown, that the longitudinal Dielectric function weakly depends on a wave vector.
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Longitudinal Dielectric Permeability into quantum non-degenerate and maxwellian plasma with frequency of collisions proportional to the module of a wave vector
arXiv: Plasma Physics, 2013Co-Authors: A. V. Latyshev, A. A. YushkanovAbstract:Formulas for the longitudinal Dielectric Permeability in quantum non-degenerate and maxwellian collisional plasma with the frequency of collisions proportional to the module of the wave vector, in Mermin's approach, are received. Equation of Shr\"{o}dinger - Boltzmann with integral of collisions relaxation type in Mermin's approach is applied. It is spent numerical and graphic comparison of the real and imaginary parts of Dielectric function of non-degenerate and maxwellian collisional quantum plasma with a constant and a variable frequencies of collisions. It is shown, that the longitudinal Dielectric function weakly depends on a wave vector.
Alexander Yushkanov - One of the best experts on this subject based on the ideXlab platform.
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Longitudinal Dielectric Permeability of a quantum degenerate plasma with a constant collisional frequency
High Temperature, 2014Co-Authors: A. V. Latyshev, Alexander YushkanovAbstract:A formula for degenerate plasma has been derived from the general formula of the Dielectric Permeability of a quantum collisional plasma. The real and imaginary parts of the Dielectric Permeability of the quantum collisional degenerate plasma have been studied graphically, and they have been compared with the real and imaginary parts of the Dielectric Permeability of the collisional classic degenerate plasma.
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Longitudinal electric conductivity and Dielectric Permeability in quantum plasma with constant collision frequency in Mermin' approach
arXiv: Plasma Physics, 2012Co-Authors: A. V. Latyshev, Alexander YushkanovAbstract:Detailed deducing of formulas for longitudinal electric conductivity and Dielectric Permeability in the quantum degenerate collisional plasma with constant collision frequency in Mermin' approach is given. The kinetic Schr\"{o}dinger-Boltzmann equation in momentum space in relaxation approximation is used. It is shown that when collision frequency of plasma particles tends to zero (plasma passes to collisionless one), the deduced formula for Dielectric function passes to the known Lindhard' formula for collisionless plasmas. It is shown that the deduced formula for Dielectric Permeability coincides with known Mermin's formula. Graphic research of the real and imaginary parts of Dielectric function is made. Graphic comparison of the real and imaginary parts of Dielectric function for quantum and classical plasma also is made. The module of derivative Dielectric function also has been investigated graphically.
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Longitudinal electric conductivity and Dielectric Permeability in quantum plasma with variable frequency of collisions in Mermin' approach
arXiv: Plasma Physics, 2012Co-Authors: A. V. Latyshev, Alexander YushkanovAbstract:Formulas for longitudinal electric conductivity and Dielectric Permeability in the quantum non-degenerate collisional plasma with the frequency of collisions depending on momentum in Mermin' approach are received. The kinetic equation in momentum space in relaxation approximation is used. It is shown that when Planck's constant tends to zero, the deduced formula passes to the corresponding formula for classical plasma. It is shown also that when frequency of collisions of particles of plasma tends to zero (plasma passes to collisionless one), the deduced formula passes to the known Lindhard' formula received for collisionless plasmas. It is shown, that when frequency of collisions is a constant, the deduced formula for Dielectric Permeability passes in known Mermin' formula.
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Longitudinal Dielectric Permeability of the quantum degenerate collisional plasmas
arXiv: Mathematical Physics, 2010Co-Authors: A. V. Latyshev, Alexander YushkanovAbstract:Dielectric Permeability of the degenerate electronic gas for the collisional plasmas is found. The kinetic equation of Wigner -- Vlasov -- Boltzmann with integral of collisions in relaxation form in coordinate space is used. We will notice that Dielectric Permeability with using of the relaxation equation in the momentum space has been received by Mermin.