Study on the Entanglement of Non-Equilibrium Finite-Spin Systems Based on Thermo-Field Dynamics

We study the Zeeman effect on entanglement of non-equilibrium finite-spin systems with external fields using a method based on thermofield dynamics (TFD). For this purpose, the extended density matrices and extended entanglement entropies of two systems with either non-competing or competing external fields are calculated according to the dissipative von Neumann equation, and the numerical results are compared. Consequently, through the “twin-peaks” oscillations of the quantum entanglement, we have illustrated the Zeeman effect on the entanglement of non-equilibrium finite-spin systems with competing external fields in the TFD algorithm.We study the Zeeman effect on entanglement of non-equilibrium finite-spin systems with external fields using a method based on thermofield dynamics (TFD). For this purpose, the extended density matrices and extended entanglement entropies of two systems with either non-competing or competing external fields are calculated according to the dissipative von Neumann equation, and the numerical results are compared. Consequently, through the “twin-peaks” oscillations of the quantum entanglement, we have illustrated the Zeeman effect on the entanglement of non-equilibrium finite-spin systems with competing external fields in the TFD algorithm.

arXiv:1509.06462International Electronic Conference on Entropy and Its Applications (ECEA)Nov 20, 20171 citation

Dissipative dynamics of entangled finite-spin systems with non-competitive external fields

弘一中川

We apply a new method based upon thermofield dynamics (TFD) to study entanglement of finite-spin systems with non-competitive external fields for both equilibrium and non-equilibrium cases. For the equilibrium finite-spin systems, the temperature dependence of the extended density matrices is derived using this method, and the effect of non-competitive external field is demonstrated. For the non-equilibrium finite-spin systems, the time dependence of the extended density matrices and the extended entanglement entropies is derived in accordance with von Noumann equation, and the dissipative dynamics of the finite-spin systems is argued. Consequently, the applicability of the TFD-based method to describe entanglement is confirmed in both equilibrium and non-equilibrium cases with the external fieds.We apply a new method based upon thermofield dynamics (TFD) to study entanglement of finite-spin systems with non-competitive external fields for both equilibrium and non-equilibrium cases. For the equilibrium finite-spin systems, the temperature dependence of the extended density matrices is derived using this method, and the effect of non-competitive external field is demonstrated. For the non-equilibrium finite-spin systems, the time dependence of the extended density matrices and the extended entanglement entropies is derived in accordance with von Noumann equation, and the dissipative dynamics of the finite-spin systems is argued. Consequently, the applicability of the TFD-based method to describe entanglement is confirmed in both equilibrium and non-equilibrium cases with the external fieds.

arXiv:1503.00052Feb 28, 20150 citations

Entanglement entropies of non-equilibrium finite-spin systems

K. Nakagawa

For the purpose of clarifying a new approach to understanding quantum entanglement using thermofield dynamics (TFD), entanglement entropies of non-equilibrium finite-spin systems are examined for both traditional and extended cases. The extended entanglement entropy, | $\hat {S}$ |⁠, is derived, and it is found that the conditions for the maximum entangled state can be obtained through this approach. The capacity of the TFD-based method to distinguish between states in quantum systems is confirmed.For the purpose of clarifying a new approach to understanding quantum entanglement using thermofield dynamics (TFD), entanglement entropies of non-equilibrium finite-spin systems are examined for both traditional and extended cases. The extended entanglement entropy, |$\hat {S}$|⁠, is derived, and it is found that the conditions for the maximum entangled state can be obtained through this approach. The capacity of the TFD-based method to distinguish between states in quantum systems is confirmed.

arXiv:1410.6988Progress of Theoretical and Experimental PhysicsFeb 6, 20153 citations

Entanglement entropies of coupled harmonic oscillators

Koichi Nakagawa

We investigate the quantum entanglement of systems of coupled harmonic oscillators on the basis of thermo-field dynamics (TFD). For coupled harmonic oscillators at equilibrium, the extended entanglement entropy is derived using the TFD method, and it is demonstrated to be controlled by temperature and coupling parameters. For non-equilibrium systems, in addition to temperature and coupling parameters, the time dependence of the extended entanglement entropy is calculated in accordance with the dissipative von Neumann equation, and the dissipative dynamics of the systems of coupled harmonic oscillators is discussed. Consequently, based on TFD, the physical parametrization of the entanglement entropies is confirmed in both the equilibrium and non-equilibrium cases of harmonic oscillator systems by means of the laws of thermodynamics.We investigate the quantum entanglement of systems of coupled harmonic oscillators on the basis of thermo-field dynamics (TFD). For coupled harmonic oscillators at equilibrium, the extended entanglement entropy is derived using the TFD method, and it is demonstrated to be controlled by temperature and coupling parameters. For non-equilibrium systems, in addition to temperature and coupling parameters, the time dependence of the extended entanglement entropy is calculated in accordance with the dissipative von Neumann equation, and the dissipative dynamics of the systems of coupled harmonic oscillators is discussed. Consequently, based on TFD, the physical parametrization of the entanglement entropies is confirmed in both the equilibrium and non-equilibrium cases of harmonic oscillator systems by means of the laws of thermodynamics.

arXiv:1601.03584Jan 14, 20167 citations

Entangled Photon Electron Following Thermo Field Dynamics Method

Ahlem Abidi

Thermo-field dynamics (TFD) is a method linking quantum information to statistical thermodynamics, focus directly on the state because the states in the tilde space in TFD play a role of tracer of the initial states by defining an extended density matrix described on the double Hilbert space. The study of quantum entanglement is more complicated, so the TFD method makes it easier, this is the subject of this paper. We use Thermo-field Dynamics method to study entanglement entropies and transition probability of a Photon-electron system between equilibrium with heat bath, and non-equilibrium, based on the dissipative von Neumann equation. Numerically, at the equilibrium and by controlling the system through temperature, we show that entanglement entropies verify the Nernst’s theorem. By increasing the quantization of a single-mode electromagnetic field, entanglement and transition probability decrease. At non-equilibrium, we show that entanglement entropies obey the second law of thermodynamics, and the emission of a photon decrease the probability of detecting the electron at a quantum levelThermo-field dynamics (TFD) is a method linking quantum information to statistical thermodynamics, focus directly on the state because the states in the tilde space in TFD play a role of tracer of the initial states by defining an extended density matrix described on the double Hilbert space. The study of quantum entanglement is more complicated, so the TFD method makes it easier, this is the subject of this paper. We use Thermo-field Dynamics method to study entanglement entropies and transition probability of a Photon-electron system between equilibrium with heat bath, and non-equilibrium, based on the dissipative von Neumann equation. Numerically, at the equilibrium and by controlling the system through temperature, we show that entanglement entropies verify the Nernst’s theorem. By increasing the quantization of a single-mode electromagnetic field, entanglement and transition probability decrease. At non-equilibrium, we show that entanglement entropies obey the second law of thermodynamics, and the emission of a photon decrease the probability of detecting the electron at a quantum level

Journal of Civil Engineering Research & TechnologyNov 30, 20250 citations

Entanglement Entropies of Coupled Harmonic Oscillators

中川, 弘一, Koichi Nakagawa

We study the quantum entanglement of systems of coupled harmonic oscillators on the basis of thermo-field dynamics (TFD).For coupled harmonic oscillators at equilibrium, the extended entanglement entropy is derived using the TFD method, and it is demonstrated to be controlled by temperature and coupling parameters.For non-equilibrium systems, in addition to temperature and coupling parameters, the time dependence of the extended entanglement entropy is calculated in accordance with the dissipative von Neumann equation, and the dissipative dynamics of the systems of coupled harmonic oscillators is discussed.Consequently, based on TFD, the physical parametrization of the entanglement entropies is confirmed in both the equilibrium and nonequilibrium cases of harmonic oscillator systems by means of the laws of thermodynamics.We study the quantum entanglement of systems of coupled harmonic oscillators on the basis of thermo-field dynamics (TFD).For coupled harmonic oscillators at equilibrium, the extended entanglement entropy is derived using the TFD method, and it is demonstrated to be controlled by temperature and coupling parameters.For non-equilibrium systems, in addition to temperature and coupling parameters, the time dependence of the extended entanglement entropy is calculated in accordance with the dissipative von Neumann equation, and the dissipative dynamics of the systems of coupled harmonic oscillators is discussed.Consequently, based on TFD, the physical parametrization of the entanglement entropies is confirmed in both the equilibrium and nonequilibrium cases of harmonic oscillator systems by means of the laws of thermodynamics.

Dec 10, 20160 citations

\hat {S}

|⁠, is derived, and it is found that the conditions for the maximum entangled state can be obtained through this approach. The capacity of the TFD-based method to distinguish between states in quantum systems is confirmed.