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Pavel A Andreev - One of the best experts on this subject based on the ideXlab platform.
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Quantum Hydrodynamics of the spinor bose einstein condensate at non zero temperatures
Physics of Fluids, 2021Co-Authors: Pavel A Andreev, Mariya Iv Trukhanova, I N MosakiAbstract:A finite temperature hydrodynamic model is derived for the spin-1 ultracold bosons by the many-particle Quantum hydrodynamic method. It is presented as the two fluid model of the Bose–Einstein condensate (BEC) and normal fluid. The continuity, Euler, spin evolution, and nematic tensor evolution equations are derived for each fluid. The linear and quadratic Zeeman effects are included. Scalar and spin–spin like short-range interactions are considered in the first order by the interaction radius. Obtained hydrodynamic equations are also represented as the set of two nonlinear Pauli equations. The spectrum of the bulk collective excitations is considered for the ferromagnetic phase in the small temperature limit. The spin wave is not affected by the presence of the small temperature in the described minimal coupling model, where the thermal part of the spin-current of the normal fluid is neglected. The two sound waves are affected by the spin evolution in the same way as the change of spectrum of the single sound wave in BEC, where speed of sound is proportional to g 1 + g 2 with gi as the interaction constants.
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Quantum Hydrodynamics of the spinor bose einstein condensate at non zero temperatures
arXiv: Quantum Gases, 2021Co-Authors: Pavel A Andreev, Mariya Iv Trukhanova, I N MosakiAbstract:Finite temperature hydrodynamic model is derived for the spin-1 ultracold bosons by the many-particle Quantum hydrodynamic method. It is presented as the two fluid model of the BEC and normal fluid. The linear and quadratic Zeeman effects are included. Scalar and spin-spin like short-range interactions are considered in the first order by the interaction radius. It is also represented as the set of two nonlinear Pauli equations. The spectrum of the bulk collective excitations is considered for the ferromagnetic phase in the small temperature limit. The spin wave is not affected by the presence of the small temperature in the described minimal coupling model, where the thermal part of the spin-current of the normal fluid is neglected. The two sound waves are affected by the spin evolution in the same way as the change of spectrum of the single sound wave in BEC, where speed of sound is proportional to $g_{1}+g_{2}$ with $g_{i}$ are the interaction constants.
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surface spin electron acoustic waves in magnetically ordered metals
Applied Physics Letters, 2016Co-Authors: Pavel A Andreev, L S KuzmenkovAbstract:Degenerate plasmas with motionless ions show existence of three surface waves: the Langmuir wave, the electromagnetic wave, and the zeroth sound. Applying the separated spin evolution Quantum Hydrodynamics to half-space plasma, we demonstrate the existence of the surface spin-electron acoustic wave (SSEAW). We study dispersion of the SSEAW. We show that there is hybridization between the surfaceLangmuir wave and the SSEAW at rather small spin polarization. In the hybridization area, the dispersion branches are located close to each other. In this area, there is a strong interaction between these waves leading to the energy exchange. Consequently, generating the Langmuir waves with the frequencies close to hybridization area we can generate the SSEAWs. Thus, we report a method of creation of the spin-electron acoustic waves.
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spin electron acoustic soliton and exchange interaction in separate spin evolution Quantum plasmas
Physics of Plasmas, 2016Co-Authors: Pavel A AndreevAbstract:Separate spin evolution Quantum Hydrodynamics is generalized to include the Coulomb exchange interaction, which is considered as interaction between the spin-down electrons being in Quantum states occupied by one electron. The generalized model is applied to study the non-linear spin-electron acoustic waves. Existence of the spin-electron acoustic soliton is demonstrated. Contributions of concentration, spin polarization, and exchange interaction to the properties of the spin electron acoustic soliton are studied.
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surface spin electron acoustic waves in magnetically ordered metals
arXiv: Plasma Physics, 2015Co-Authors: Pavel A Andreev, L S KuzmenkovAbstract:Degenerate plasmas with motionless ions show existence of three surface waves: the Langmuir wave, the electromagnetic wave, and the zeroth sound. Applying the separated spin evolution Quantum Hydrodynamics to half-space plasma we demonstrate the existence of the surface spin-electron acoustic wave (SSEAW). We study dispersion of the SSEAW. We show that there is hybridization between the surface Langmuir wave and the SSEAW at rather small spin polarization. In the hybridization area the dispersion branches are located close to each other. In this area there is a strong interaction between these waves leading to the energy exchange. Consequently, generating the Langmuir waves with the frequencies close to hybridization area we can generate the SSEAWs. Thus, we report a method of creation of the SEAWs.
Mariya Iv Trukhanova - One of the best experts on this subject based on the ideXlab platform.
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Quantum Hydrodynamics of the spinor bose einstein condensate at non zero temperatures
Physics of Fluids, 2021Co-Authors: Pavel A Andreev, Mariya Iv Trukhanova, I N MosakiAbstract:A finite temperature hydrodynamic model is derived for the spin-1 ultracold bosons by the many-particle Quantum hydrodynamic method. It is presented as the two fluid model of the Bose–Einstein condensate (BEC) and normal fluid. The continuity, Euler, spin evolution, and nematic tensor evolution equations are derived for each fluid. The linear and quadratic Zeeman effects are included. Scalar and spin–spin like short-range interactions are considered in the first order by the interaction radius. Obtained hydrodynamic equations are also represented as the set of two nonlinear Pauli equations. The spectrum of the bulk collective excitations is considered for the ferromagnetic phase in the small temperature limit. The spin wave is not affected by the presence of the small temperature in the described minimal coupling model, where the thermal part of the spin-current of the normal fluid is neglected. The two sound waves are affected by the spin evolution in the same way as the change of spectrum of the single sound wave in BEC, where speed of sound is proportional to g 1 + g 2 with gi as the interaction constants.
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Quantum Hydrodynamics of the spinor bose einstein condensate at non zero temperatures
arXiv: Quantum Gases, 2021Co-Authors: Pavel A Andreev, Mariya Iv Trukhanova, I N MosakiAbstract:Finite temperature hydrodynamic model is derived for the spin-1 ultracold bosons by the many-particle Quantum hydrodynamic method. It is presented as the two fluid model of the BEC and normal fluid. The linear and quadratic Zeeman effects are included. Scalar and spin-spin like short-range interactions are considered in the first order by the interaction radius. It is also represented as the set of two nonlinear Pauli equations. The spectrum of the bulk collective excitations is considered for the ferromagnetic phase in the small temperature limit. The spin wave is not affected by the presence of the small temperature in the described minimal coupling model, where the thermal part of the spin-current of the normal fluid is neglected. The two sound waves are affected by the spin evolution in the same way as the change of spectrum of the single sound wave in BEC, where speed of sound is proportional to $g_{1}+g_{2}$ with $g_{i}$ are the interaction constants.
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spin current evolution in the separated spin up and spin down Quantum Hydrodynamics
Physics Letters A, 2015Co-Authors: Mariya Iv TrukhanovaAbstract:Abstract We have developed a method of Quantum Hydrodynamics (QHD) that describes particles with spin-up and with spin-down in separate. We have derived the equation of the spin current evolution as a part of the set of the Quantum Hydrodynamics equations that treat particles with different projection of spin on the preferable direction as two different species. We have studied orthogonal propagation of waves in the external magnetic field and determined the contribution of Quantum corrections due to the Bohm potential and to magnetization energy of particles with different projections of spin in the spin-current wave dispersion. We have analyzed the limits of weak and strong magnetic fields.
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spin and polarization waves in a system of paramagnetic particles with an intrinsic dipole moment
International Journal of Modern Physics B, 2012Co-Authors: Mariya Iv TrukhanovaAbstract:We explicate a derivation of a general system of Quantum Hydrodynamics (QHD) equations for the study of the non-equilibrium processes. Fundamental QHD equations for neutral paramagnetic particles with the own electric dipole moment (EDM) were derived from the many-particle Schrodinger equation. The fact that the influence of spin–spin, dipole–dipole and spin–orbital interaction between particles was taken into account. The problem of definition of spin-waves and polarization waves spectrum in 2D system for the molecules with intrinsic magnetic moments (IMM) and EDM were theoretically investigated and solved for the system of nitric oxide gas in the external electromagnetic fields. The polarization dynamics in system of neutral magnetic and polarized particles is shown to cause formation of a new type of waves as well as changes in the dispersion characteristics of already known waves. Moreover we found the contribution of spin–orbital interaction between gas particles to the elementary excitations and shown that spin–orbital interaction leads to the emergence of magnetization and polarization waves.
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Quantum Hydrodynamics approach to the formation of waves in polarized two dimensional systems of charged and neutral particles
Physical Review B, 2011Co-Authors: Pavel A Andreev, L S Kuzmenkov, Mariya Iv TrukhanovaAbstract:In this paper we explicate a method of Quantum Hydrodynamics (QHD) for the study of the Quantum evolution of a system of polarized particles. Though we focused primarily on the two-dimension physical systems, the method is valid for three-dimension and one-dimension systems too. The presented method is based upon the Schrodinger equation. Fundamental QHD equations for charged and neutral particles were derived from the many-particle microscopic Schrodinger equation. The fact that particles possess the electric dipole moment (EDM) was taken into account. Basing upon the QHD equation system we present the derivation of the non-linear Schrodinger equation (NLSE) for a system of polarized particles. A generalized London equation was constructed for heterogeneous systems. The explicated QHD approach was used to study dispersion characteristics of various physical systems. We analyzed dispersion of waves in a two-dimension (2D) ion and hole gas placed into an external electric field which is orthogonal to the gas plane. Elementary excitations in a system of neutral polarized particles were studied for 1D, 2D and 3D cases. The polarization dynamics in systems of both neutral and charged particles is shown to cause formation of a new type of waves as well as changes in the dispersion characteristics of already known waves. We also analyzed wave dispersion in 2D exciton systems, in 2D electron-ion plasma and 2D electron-hole plasma. Generation of waves in 3D system neutral particles with EDM by means of the beam of electrons and neutral polarized particles is invest igated.
M Bonitz - One of the best experts on this subject based on the ideXlab platform.
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Quantum Hydrodynamics for plasmas quo vadis
Physics of Plasmas, 2019Co-Authors: M Bonitz, Zh A Moldabekov, T S RamazanovAbstract:Quantum plasmas are an important topic in astrophysics and high pressure laboratory physics for more than 50 years. In addition, many condensed matter systems, including the electron gas in metals, metallic nanoparticles, or electron-hole systems in semiconductors and heterostructures, exhibit—to some extent—plasmalike behavior. Among the key theoretical approaches that have been applied to these systems are Quantum kinetic theory, Green function theory, Quantum Monte Carlo, semiclassical and Quantum molecular dynamics, and more recently, density functional theory simulations. These activities are in close contact with the experiments and have firmly established themselves in the fields of plasma physics, astrophysics, and condensed matter physics. About two decades ago, a second branch of Quantum plasma theory emerged that is based on a Quantum fluid description and has attracted a substantial number of researchers. The focus of these studies has been on collective oscillations and linear and nonlinear waves in Quantum plasmas. Even though these papers pretend to address the same physical systems as the more traditional papers mentioned above, the former appear to form a rather closed community that is largely isolated from the rest of the field. The Quantum Hydrodynamics (QHD) results have—with a few exceptions—not found application in astrophysics or in experiments in condensed matter physics. Moreover, these results practically did not have any impact on the former Quantum plasma theory community. One reason is the unknown accuracy of the QHD for dense plasmas. In this paper, we present a novel derivation, starting from reduced density operators that clearly point to the deficiencies of QHD, and we outline possible improvements. It is also to be noted that some of the QHD results have attracted negative attention being criticized as unphysical. Examples include the prediction of “novel attractive forces” between protons in an equilibrium Quantum plasma, the notion of “spinning Quantum plasmas,” or the new field of “Quantum dusty plasmas.” In the present article, we discuss the latter system in some detail because it is a particularly disturbing case of formal theoretical investigations that are detached from physical reality despite bold and unproven claims of importance for, e.g., dense astrophysical plasmas or microelectronics. We stress that these deficiencies are not a problem of QHD itself, which is a powerful and efficient method, but rather are due to ignorance of its properties and limitations. We analyze the common flaws of these works and come up with suggestions to improve the situation of QHD applications to Quantum plasmas.
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theoretical foundations of Quantum Hydrodynamics for plasmas
Physics of Plasmas, 2018Co-Authors: Zh A Moldabekov, M Bonitz, T S RamazanovAbstract:Quantum Hydrodynamics (QHD) theory for finite temperature plasmas is consistently derived in the framework of the local density approximation of the free energy with first order density gradient correction. Previously known results are revised and improved with a clear description of the underlying approximations. A fully non-local Bohm potential, which goes beyond all previous results and is linked to the electron polarization function in the random phase approximation, for the QHD model is presented. The dynamic QHD exchange correlation potential is introduced in the framework of local field corrections and considered for the case of the relaxation time approximation. Finally, the range of applicability of the QHD is discussed.
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theoretical foundations of Quantum Hydrodynamics for plasmas
arXiv: Plasma Physics, 2017Co-Authors: Zh A Moldabekov, M Bonitz, T S RamazanovAbstract:Beginning from the semiclassical Hamiltonian, the Fermi pressure and Bohm potential for the Quantum Hydrodynamics application (QHD) at finite temperature are consistently derived in the framework of the local density approximation with the first order density gradient correction. Previously known results are revised and improved with a clear description of the underlying approximations. A fully non-local Bohm potential, which goes beyond of all previous results and is linked to the electron polarization function in the random phase approximation, for the QHD model is presented. The dynamic QHD exchange correlation potential is introduced in the framework of local field corrections, and considered for the case of the relaxation time approximation. Finally, the range of applicability of the QHD is discussed.
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Quantum Hydrodynamics for plasmas a thomas fermi theory perspective
Contributions To Plasma Physics, 2015Co-Authors: Frank Graziani, David Michta, M BonitzAbstract:The idea to describe Quantum systems within a hydrodynamic framework (Quantum Hydrodynamics, QHD) goes back to Madelung and Bohm. While such a description is formally exact for a single particle, more recently the concept has been applied to many-particle systems by Manfredi and Haas [Phys. Rev. B 64, 075316 (2001)] and received high popularity in parts of the Quantum plasma community. Thereby, often the applicability limits of these equations are ignored, giving rise to unphysical predictions. Here we demonstrate that modified QHD equations for plasmas can be derived from Thomas-Fermi theory including gradient corrections. This puts QHD on firm grounds. At the same time this derivation yields a different prefactor, γ = (D – 2/3D), in front of the Quantum (Bohm) potential which depends on the system dimensionality D. Our approach allows one to identify the limitations of QHD and to outline systematic improvements. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
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reply to comment on attractive forces between ions in Quantum plasmas failure of linearized Quantum Hydrodynamics
Physical Review E, 2013Co-Authors: M Bonitz, E Pehlke, Tim SchoofAbstract:This is the last of a series of three papers. In the first [Phys. Rev. E 87, 033105 (2013)], the same authors presented a critical analysis of the prediction of ``novel attractive forces'' between protons in dense hydrogen put forward by Shukla and Eliasson in a recent Letter [Phys. Rev. Lett. 108, 165007 (2012)]. Based on ab initio density functional theory (DFT) calculations and general considerations, it was shown that no such force exists. In the second of the three papers [Phys. Rev. E 87, 037101 (2013)], Shukla, Eliasson, and Akbari-Moghanjoughi (SEA) rejected this analysis. SEA did not discuss our arguments but claimed that the discrepancy between their Quantum hydrodynamic model (QHD) and DFT is due to a failure of the latter. It is the purpose of the present Reply to demonstrate that this claim is incorrect because DFT is more accurate than QHD, by construction.
Christopher Mudry - One of the best experts on this subject based on the ideXlab platform.
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topological bf theory of the Quantum Hydrodynamics of incompressible polar fluids
Bulletin of the American Physical Society, 2015Co-Authors: Apoorv Tiwari, Xiao Chen, Titus Neupert, Luiz Santos, Shinsei Ryu, Claudio Chamon, Christopher MudryAbstract:Apoorv Tiwari, Xiao Chen, Titus Neupert, Luiz H. Santos, Shinsei Ryu, Claudio Chamon, and Christopher Mudry 1 Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green St, Urbana IL 61801 2 Princeton Center for Theoretical Science, Princeton University, Princeton, New Jersey 08544, USA 3 Perimeter Institute for Theoretical Physics, Waterloo, ON, N2L 2Y5, Canada 4 Physics Department, Boston University, Boston, Massachusetts 02215, USA 5 Condensed Matter Theory Group, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland (Dated: January 12, 2015)
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topological bf theory of the Quantum Hydrodynamics of incompressible polar fluids
Physical Review B, 2014Co-Authors: Apoorv Tiwari, Xiao Chen, Titus Neupert, Luiz Santos, Shinsei Ryu, Claudio Chamon, Christopher MudryAbstract:We analyze a hydrodynamical model of a polar fluid in (3+1)-dimensional spacetime. We explore a spacetime symmetry -- volume preserving diffeomorphisms -- to construct an effective description of this fluid in terms of a topological BF theory. The two degrees of freedom of the BF theory are associated to the mass (charge) flows of the fluid and its polarization vorticities. We discuss the quantization of this hydrodynamic theory, which generically allows for fractionalized excitations. We propose an extension of the Girvin-MacDonald-Platzman algebra to (3+1)-dimensional spacetime by the inclusion of the vortex-density operator in addition to the usual charge density operator and show that the same algebra is obeyed by massive Dirac fermions that represent the bulk of $\mathbb{Z}^{\,}_{2}$ topological insulators in three-dimensional space.
Zh A Moldabekov - One of the best experts on this subject based on the ideXlab platform.
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Quantum Hydrodynamics for plasmas quo vadis
Physics of Plasmas, 2019Co-Authors: M Bonitz, Zh A Moldabekov, T S RamazanovAbstract:Quantum plasmas are an important topic in astrophysics and high pressure laboratory physics for more than 50 years. In addition, many condensed matter systems, including the electron gas in metals, metallic nanoparticles, or electron-hole systems in semiconductors and heterostructures, exhibit—to some extent—plasmalike behavior. Among the key theoretical approaches that have been applied to these systems are Quantum kinetic theory, Green function theory, Quantum Monte Carlo, semiclassical and Quantum molecular dynamics, and more recently, density functional theory simulations. These activities are in close contact with the experiments and have firmly established themselves in the fields of plasma physics, astrophysics, and condensed matter physics. About two decades ago, a second branch of Quantum plasma theory emerged that is based on a Quantum fluid description and has attracted a substantial number of researchers. The focus of these studies has been on collective oscillations and linear and nonlinear waves in Quantum plasmas. Even though these papers pretend to address the same physical systems as the more traditional papers mentioned above, the former appear to form a rather closed community that is largely isolated from the rest of the field. The Quantum Hydrodynamics (QHD) results have—with a few exceptions—not found application in astrophysics or in experiments in condensed matter physics. Moreover, these results practically did not have any impact on the former Quantum plasma theory community. One reason is the unknown accuracy of the QHD for dense plasmas. In this paper, we present a novel derivation, starting from reduced density operators that clearly point to the deficiencies of QHD, and we outline possible improvements. It is also to be noted that some of the QHD results have attracted negative attention being criticized as unphysical. Examples include the prediction of “novel attractive forces” between protons in an equilibrium Quantum plasma, the notion of “spinning Quantum plasmas,” or the new field of “Quantum dusty plasmas.” In the present article, we discuss the latter system in some detail because it is a particularly disturbing case of formal theoretical investigations that are detached from physical reality despite bold and unproven claims of importance for, e.g., dense astrophysical plasmas or microelectronics. We stress that these deficiencies are not a problem of QHD itself, which is a powerful and efficient method, but rather are due to ignorance of its properties and limitations. We analyze the common flaws of these works and come up with suggestions to improve the situation of QHD applications to Quantum plasmas.
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theoretical foundations of Quantum Hydrodynamics for plasmas
Physics of Plasmas, 2018Co-Authors: Zh A Moldabekov, M Bonitz, T S RamazanovAbstract:Quantum Hydrodynamics (QHD) theory for finite temperature plasmas is consistently derived in the framework of the local density approximation of the free energy with first order density gradient correction. Previously known results are revised and improved with a clear description of the underlying approximations. A fully non-local Bohm potential, which goes beyond all previous results and is linked to the electron polarization function in the random phase approximation, for the QHD model is presented. The dynamic QHD exchange correlation potential is introduced in the framework of local field corrections and considered for the case of the relaxation time approximation. Finally, the range of applicability of the QHD is discussed.
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theoretical foundations of Quantum Hydrodynamics for plasmas
arXiv: Plasma Physics, 2017Co-Authors: Zh A Moldabekov, M Bonitz, T S RamazanovAbstract:Beginning from the semiclassical Hamiltonian, the Fermi pressure and Bohm potential for the Quantum Hydrodynamics application (QHD) at finite temperature are consistently derived in the framework of the local density approximation with the first order density gradient correction. Previously known results are revised and improved with a clear description of the underlying approximations. A fully non-local Bohm potential, which goes beyond of all previous results and is linked to the electron polarization function in the random phase approximation, for the QHD model is presented. The dynamic QHD exchange correlation potential is introduced in the framework of local field corrections, and considered for the case of the relaxation time approximation. Finally, the range of applicability of the QHD is discussed.