We propose a scheme for dissipative preparation of maximal entanglement in a two-qubit Heisenberg... more We propose a scheme for dissipative preparation of maximal entanglement in a two-qubit Heisenberg XXZ model interacting asymmetrically with two independent boson thermal reservoirs with different temperature. One reservoir is common to both qubits, while the other is connected with just one qubit. We analytically and numerically investigate the steady-state entanglement of the qubits, based on the Markovian quantum master equation. We study the influence of the inherent asymmetry induced by the asymmetrically couplings of qubits to the reservoirs, on the steady-state entanglement of the qubits. While the temperature gradient of reservoirs generally deteriorate quantum correlations, we show that in the presence of the inherent asymmetry, the maximal entanglement can revive by increasing temperature gradient, at high base temperature of the reservoirs. We find that by turning on the asymmetry, perfect rectification can be achieved without introducing any additional asymmetry to the system. We also discover that the obtained perfect rectification is associated with maximizing of the steady-state entanglement.
We study a quantum heat engine (QHE) with a working medium described by a parity-deformed Jaynes–... more We study a quantum heat engine (QHE) with a working medium described by a parity-deformed Jaynes–Cummings (JC) model consisting of two identical two-level atoms interacting with a single-mode para-Bose field in a cavity. Compared to the standard two-atom JC model, this model introduces the action of a specific local classical field as an external control. This QHE operates under a quantum Otto cycle, where the working substance interacts with two reservoirs at different temperatures through four stages including two quantum isochoric processes and two quantum adiabatic processes. We investigate influence of the local external classical fields on the positive work condition as well as the efficiency of the engine, with emphasis on the control role of the local external classical fields. In the absence of local classical fields, we analytically show that work can not be extracted at low-temperature reservoirs, while a remarkable work is extracted for any temperature under the local classical fields. Meanwhile, we show that the efficiency of our engine reaches the classical Carnot value in the low-temperature regime. We also study the thermal atom-atom entanglement at the end of isochoric stages and show that it will be maintained by adjusting the intensity of the local classical fields. Interestingly, we find that the reduction of the thermal atom-atom entanglement during the cold bath stage acts as a resource for positive work extraction.
We consider a parity-deformed Jaynes–Cummings model (JCM) consisting of two identical two-level a... more We consider a parity-deformed Jaynes–Cummings model (JCM) consisting of two identical two-level atoms interacting with a single-mode para-Bose field in a cavity. Compared to the standard JCM, this model introduces the action of a specific local classical field as an external control which can be simulated through an intensity-dependent two-atom JCM with a particular intensity-dependent function. The conservation of the total excitation number and overall parity provides a complete number parity basis for the Hilbert space of the system. In this basis, the matrix representation of the system’s Hamiltonian becomes block diagonal. The corresponding eigenvalues and eigenstates of the system are then analytically calculated by diagonalizing the block matrices. In continuum, we investigate the dynamical evolution of some physical properties such as entanglement, atomic inversion, photon statistics and atomic squeezing in the parity representation, with emphasis on the control role of the local external classical fields. In addition, in the presence of the cavity decay, we study the effect of cavity dissipation on the quantum dynamics of the system. In the ideal case (without the cavity dissipation), we show that the initial states of the system with even–odd parity manifest qualitatively distinct control role of the local external classical fields on the dynamical behavior of the physical properties. In the dissipation regime, we show that the control of local classical fields has the general effect to improve the stabilization of the quantum properties of the system generated during the time evolution.
The Dirac-like quasiparticles in honeycomb graphene lattice are taken to possess a non-zero effec... more The Dirac-like quasiparticles in honeycomb graphene lattice are taken to possess a non-zero effective mass. The charge carriers involve to interact with a femtosecond strong laser pulse. Due to the scattering time of electrons in graphene ([Formula: see text]10–100 fs), the one femtosecond optical pulse is used to establish the coherence effect and, consequently, it can be realized to use the time-dependent Schrödinger equation for electron coupled with strong electromagnetic field. Generalized wave vector of relativistic electrons interacting with electric field of laser pulse causes to obtain a time-dependent electric dipole matrix element. Using the coupled differential equations of a two-state system of graphene, the density of probability of population transition between valence (VB) and conduction bands (CB) of gapped graphene is calculated. In particular, the effect of bandgap energy on dipole matrix elements at the Dirac points and resulting CB population (CBP) is investigat...
We propose a scheme for dissipative preparation of maximal entanglement in a two-qubit Heisenberg... more We propose a scheme for dissipative preparation of maximal entanglement in a two-qubit Heisenberg XXZ model interacting asymmetrically with two independent boson thermal reservoirs with different temperature. One reservoir is common to both qubits, while the other is connected with just one qubit. We analytically and numerically investigate the steady-state entanglement of the qubits, based on the Markovian quantum master equation. We study the influence of the inherent asymmetry induced by the asymmetrically couplings of qubits to the reservoirs, on the steady-state entanglement of the qubits. While the temperature gradient of reservoirs generally deteriorate quantum correlations, we show that in the presence of the inherent asymmetry, the maximal entanglement can revive by increasing temperature gradient, at high base temperature of the reservoirs. We find that by turning on the asymmetry, perfect rectification can be achieved without introducing any additional asymmetry to the system. We also discover that the obtained perfect rectification is associated with maximizing of the steady-state entanglement.
We consider a parity-deformed Jaynes-Cummings model (JCM) consisting of two identical two-level a... more We consider a parity-deformed Jaynes-Cummings model (JCM) consisting of two identical two-level atoms interacting with a single-mode para-Bose field in a cavity. Compared to the standard JCM, this model introduces the action of a specific local classical field as an external control which can be simulated through an intensity-dependent two-atom JCM with a particular intensity-dependent function. The conservation of the total excitation number and overall parity provides a complete number parity basis for the Hilbert space of the system. In this basis, the matrix representation of the system's Hamiltonian becomes block diagonal. The corresponding eigenvalues and eigenstates of the system are then analytically calculated by diagonalizing the block matrices. In continuum, we investigate the dynami-cal evolution of some physical properties such as entanglement, atomic inversion, photon statistics and atomic squeezing in the parity representation, with emphasis on the control role of the local external classical fields. In addition, in the presence of the cavity decay, we study the effect of cavity dissipation on the quantum dynamics of the system. In the ideal case (without the cavity dissipation), we show that the initial states of the system with even-odd parity manifest qualitatively distinct control role of the local external classical fields on the dynamical behavior of the physical properties. In the dissipation regime, we show that the control of local classical fields has the general effect to improve the stabilization of the quantum properties of the system generated during the time evolution.
The Dirac-like quasiparticles in honeycomb graphene lattice are taken to possess a non-zero effec... more The Dirac-like quasiparticles in honeycomb graphene lattice are taken to possess a non-zero effective mass. The charge carriers involve to interact with a femtosecond strong laser pulse. Due to the scattering time of electrons in graphene (τ ≈ 10-100 fs), the one femtosecond optical pulse is used to establish the coherence effect and, consequently, it can be realized to use the time-dependent Schrödinger equation for electron coupled with strong electromagnetic field. Generalized wave vector of relativistic electrons interacting with electric field of laser pulse causes to obtain a time-dependent electric dipole matrix element. Using the coupled differential equations of a two-state system of graphene, the density of probability of population transition between valence (VB) and conduction bands (CB) of gapped graphene is calculated. In particular, the effect of bandgap energy on dipole matrix elements at the Dirac points and resulting CB population (CBP) is investigated. The irreversible electron dynamics is achieved when the optical pulse end. Increasing the energy gap of graphene results in decreasing the maximum CBP.
We propose a scheme for dissipative preparation of maximal entanglement in a two-qubit Heisenberg... more We propose a scheme for dissipative preparation of maximal entanglement in a two-qubit Heisenberg XXZ model interacting asymmetrically with two independent boson thermal reservoirs with different temperature. One reservoir is common to both qubits, while the other is connected with just one qubit. We analytically and numerically investigate the steady-state entanglement of the qubits, based on the Markovian quantum master equation. We study the influence of the inherent asymmetry induced by the asymmetrically couplings of qubits to the reservoirs, on the steady-state entanglement of the qubits. While the temperature gradient of reservoirs generally deteriorate quantum correlations, we show that in the presence of the inherent asymmetry, the maximal entanglement can revive by increasing temperature gradient, at high base temperature of the reservoirs. We find that by turning on the asymmetry, perfect rectification can be achieved without introducing any additional asymmetry to the system. We also discover that the obtained perfect rectification is associated with maximizing of the steady-state entanglement.
We study a quantum heat engine (QHE) with a working medium described by a parity-deformed Jaynes–... more We study a quantum heat engine (QHE) with a working medium described by a parity-deformed Jaynes–Cummings (JC) model consisting of two identical two-level atoms interacting with a single-mode para-Bose field in a cavity. Compared to the standard two-atom JC model, this model introduces the action of a specific local classical field as an external control. This QHE operates under a quantum Otto cycle, where the working substance interacts with two reservoirs at different temperatures through four stages including two quantum isochoric processes and two quantum adiabatic processes. We investigate influence of the local external classical fields on the positive work condition as well as the efficiency of the engine, with emphasis on the control role of the local external classical fields. In the absence of local classical fields, we analytically show that work can not be extracted at low-temperature reservoirs, while a remarkable work is extracted for any temperature under the local classical fields. Meanwhile, we show that the efficiency of our engine reaches the classical Carnot value in the low-temperature regime. We also study the thermal atom-atom entanglement at the end of isochoric stages and show that it will be maintained by adjusting the intensity of the local classical fields. Interestingly, we find that the reduction of the thermal atom-atom entanglement during the cold bath stage acts as a resource for positive work extraction.
We consider a parity-deformed Jaynes–Cummings model (JCM) consisting of two identical two-level a... more We consider a parity-deformed Jaynes–Cummings model (JCM) consisting of two identical two-level atoms interacting with a single-mode para-Bose field in a cavity. Compared to the standard JCM, this model introduces the action of a specific local classical field as an external control which can be simulated through an intensity-dependent two-atom JCM with a particular intensity-dependent function. The conservation of the total excitation number and overall parity provides a complete number parity basis for the Hilbert space of the system. In this basis, the matrix representation of the system’s Hamiltonian becomes block diagonal. The corresponding eigenvalues and eigenstates of the system are then analytically calculated by diagonalizing the block matrices. In continuum, we investigate the dynamical evolution of some physical properties such as entanglement, atomic inversion, photon statistics and atomic squeezing in the parity representation, with emphasis on the control role of the local external classical fields. In addition, in the presence of the cavity decay, we study the effect of cavity dissipation on the quantum dynamics of the system. In the ideal case (without the cavity dissipation), we show that the initial states of the system with even–odd parity manifest qualitatively distinct control role of the local external classical fields on the dynamical behavior of the physical properties. In the dissipation regime, we show that the control of local classical fields has the general effect to improve the stabilization of the quantum properties of the system generated during the time evolution.
The Dirac-like quasiparticles in honeycomb graphene lattice are taken to possess a non-zero effec... more The Dirac-like quasiparticles in honeycomb graphene lattice are taken to possess a non-zero effective mass. The charge carriers involve to interact with a femtosecond strong laser pulse. Due to the scattering time of electrons in graphene ([Formula: see text]10–100 fs), the one femtosecond optical pulse is used to establish the coherence effect and, consequently, it can be realized to use the time-dependent Schrödinger equation for electron coupled with strong electromagnetic field. Generalized wave vector of relativistic electrons interacting with electric field of laser pulse causes to obtain a time-dependent electric dipole matrix element. Using the coupled differential equations of a two-state system of graphene, the density of probability of population transition between valence (VB) and conduction bands (CB) of gapped graphene is calculated. In particular, the effect of bandgap energy on dipole matrix elements at the Dirac points and resulting CB population (CBP) is investigat...
We propose a scheme for dissipative preparation of maximal entanglement in a two-qubit Heisenberg... more We propose a scheme for dissipative preparation of maximal entanglement in a two-qubit Heisenberg XXZ model interacting asymmetrically with two independent boson thermal reservoirs with different temperature. One reservoir is common to both qubits, while the other is connected with just one qubit. We analytically and numerically investigate the steady-state entanglement of the qubits, based on the Markovian quantum master equation. We study the influence of the inherent asymmetry induced by the asymmetrically couplings of qubits to the reservoirs, on the steady-state entanglement of the qubits. While the temperature gradient of reservoirs generally deteriorate quantum correlations, we show that in the presence of the inherent asymmetry, the maximal entanglement can revive by increasing temperature gradient, at high base temperature of the reservoirs. We find that by turning on the asymmetry, perfect rectification can be achieved without introducing any additional asymmetry to the system. We also discover that the obtained perfect rectification is associated with maximizing of the steady-state entanglement.
We consider a parity-deformed Jaynes-Cummings model (JCM) consisting of two identical two-level a... more We consider a parity-deformed Jaynes-Cummings model (JCM) consisting of two identical two-level atoms interacting with a single-mode para-Bose field in a cavity. Compared to the standard JCM, this model introduces the action of a specific local classical field as an external control which can be simulated through an intensity-dependent two-atom JCM with a particular intensity-dependent function. The conservation of the total excitation number and overall parity provides a complete number parity basis for the Hilbert space of the system. In this basis, the matrix representation of the system's Hamiltonian becomes block diagonal. The corresponding eigenvalues and eigenstates of the system are then analytically calculated by diagonalizing the block matrices. In continuum, we investigate the dynami-cal evolution of some physical properties such as entanglement, atomic inversion, photon statistics and atomic squeezing in the parity representation, with emphasis on the control role of the local external classical fields. In addition, in the presence of the cavity decay, we study the effect of cavity dissipation on the quantum dynamics of the system. In the ideal case (without the cavity dissipation), we show that the initial states of the system with even-odd parity manifest qualitatively distinct control role of the local external classical fields on the dynamical behavior of the physical properties. In the dissipation regime, we show that the control of local classical fields has the general effect to improve the stabilization of the quantum properties of the system generated during the time evolution.
The Dirac-like quasiparticles in honeycomb graphene lattice are taken to possess a non-zero effec... more The Dirac-like quasiparticles in honeycomb graphene lattice are taken to possess a non-zero effective mass. The charge carriers involve to interact with a femtosecond strong laser pulse. Due to the scattering time of electrons in graphene (τ ≈ 10-100 fs), the one femtosecond optical pulse is used to establish the coherence effect and, consequently, it can be realized to use the time-dependent Schrödinger equation for electron coupled with strong electromagnetic field. Generalized wave vector of relativistic electrons interacting with electric field of laser pulse causes to obtain a time-dependent electric dipole matrix element. Using the coupled differential equations of a two-state system of graphene, the density of probability of population transition between valence (VB) and conduction bands (CB) of gapped graphene is calculated. In particular, the effect of bandgap energy on dipole matrix elements at the Dirac points and resulting CB population (CBP) is investigated. The irreversible electron dynamics is achieved when the optical pulse end. Increasing the energy gap of graphene results in decreasing the maximum CBP.
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