The detailed analysis of the two-mode quadrature squeezing and statistical properties of light ge... more The detailed analysis of the two-mode quadrature squeezing and statistical properties of light generated by a nondegenerate three-level laser which has a parametric amplifier and coupled with a thermal reservoir is executed. The combination of the master equation and the stochastic differential equation is presented to study the nonclassical features of the light generated by the quantum system. Moreover, with the aid the resulting solutions together with the correlation properties of noise operators, we calculated the quadrature squeezing, entanglement, and mean number of photon pairs of the cavity light. It is found that the external small-amplitude driving radiation induces a strong correlation between the top and bottom states of three-level atoms to produce a high degree of squeezing. Moreover, the presence of a parametric amplifier is found to enhance the degree of squeezing of the cavity light. We have also established that an increase in the mean thermal photon number appear...
We analyse the entanglement of the light produced by a three-level laser whose cavity contains a ... more We analyse the entanglement of the light produced by a three-level laser whose cavity contains a parametric amplifier, with the cavity mode driven by the coherent light and coupled to a squeezed vacuum reservoir. Employing stochastic differential equations associated with the normal ordering resulted from the pertinent master equation, the quadrature variances and entanglement of the two-mode light are obtained and photon statistics of the two-light modes is discussed. It is found that the three-level laser generates squeezed light under certain conditions, with maximum intracavity squeezing being 89.7% below the coherent state level. We also show that the parametric amplifier enhances the mean photon number and photon number correlation.
We have analyzed the squeezing and statistical properties of the cavity light beam produced by a ... more We have analyzed the squeezing and statistical properties of the cavity light beam produced by a coherently driven degenerate three-level laser with a degenerate parametric amplifier (DPA) in an open cavity and coupled to a vacuum reservoir via a single-port mirror. We have carried out our analysis by putting the noise operators associated with the vacuum reservoir in normal order. Applying the solutions of the equations of evolution for the expectation values of the atomic operators and the quantum Langevin equation for the cavity mode operator, the mean photon number and the quadrature squeezing of the cavity light are calculated. And a large part of the mean photon number is confined in a relatively small frequency interval. Furthermore, we also obtain the antinormally ordered characteristic function defined in the Heisenberg picture. With the aid of the resulting characteristic function, we determine the function which is then used to calculate the photon number distribution.
Levofloxacin (LVF) and norfloxacin (NRF) are a group of fluoroquinolone antibiotics, broad spectr... more Levofloxacin (LVF) and norfloxacin (NRF) are a group of fluoroquinolone antibiotics, broad spectrum used to treat various infections caused by many bacterial species. The drugs contain functional groups which control the type and degree of interaction with different solvents. In this research, the ground and excited state dipole moments of LVF and NRF drugs were estimated using solvatochromic effects and computational work. The dipole moments were estimated from absorption and emission spectra in polar and nonpolar solvents using Bakhshiev’s, Kawski–Chamma–Viallet, Lippert–Mataga, and Reichardt models. The results indicated the emission spectra are more strongly affected by solvent polarity than the absorption spectra. The calculated excited state dipole moment is larger than that of the ground state, indicating that the probe compounds are significantly more polarized in the excited state than in the ground state. From computational work, the HOMO-LUMO energy band gap, the dipole m...
In this paper, the quantum properties of a two-level atom interaction with squeezed vacuum reserv... more In this paper, the quantum properties of a two-level atom interaction with squeezed vacuum reservoir is throughly analyzed. With the aid of the interaction Hamiltonian and the master equation, we obtain the time evolution of the expectation values of the atomic operators. Employing the steady-state solution of these equations, we calculate the power spectrum and the second-order correlation function for the interaction of two-level atom with squeezed vacuum reservoir. It is found that the half width of the power spectrum of the light increases with the squeeze parameter, . Furthermore, in the absence of decay constant and interaction time, it enhances the probability for the atom to be in the upper level.
The role of phase fluctuation on the quantum and statistical features of the two-mode radiation p... more The role of phase fluctuation on the quantum and statistical features of the two-mode radiation produced by a correlated emission laser which is externally injected with squeezed radiation is discussed. The considered atoms are prepared in the ground and excited states with equal probabilities before being injected into the laser cavity, and an external coherent field generates the atomic coherence that leads to the non-classical features in the quantum system. A non-degenerate parametric amplifier is also introduced into the laser cavity which is coupled to a two-mode squeezed environment. It is found that the quantum and statistical properties are very sensitive to and highly altered by the phase fluctuation when the strength of the external coherent field is weak. On the contrary, the external coherent field entirely overcomes the influence of phase fluctuation for the amplitude of the external coherent field that lies in the strong pumping regime so that the strength of squeezin...
The concept of relativistic multipole expansion is applied to determine the multipole moments of ... more The concept of relativistic multipole expansion is applied to determine the multipole moments of the electric potential of a charged system moving at constant velocity with respect to a stationary observer. A system of discrete point charges and a charged plate of uniform surface charge density were considered for analysis. For relativistic considerations, two reference frames: namely S and SËŠ were chosen. SËŠ, which contains the charged system, is moving with constant velocity relative to frame S, to which stationary observer is attached. For easy comparison, both multipole expansions are expressed in terms of the coordinates of the SËŠ frame. The two observers in S and SËŠ, in general, calculate different expressions of multipole expansion for the same charged system because of Lorentz contraction effect. The multipole terms of the potential evaluated by the observer in S is time dependent. This shows that there are also magnetic effects, which are not observed by an observer in SËŠ.
Applying the combination of the master and stochastic differential equations, we investigate in d... more Applying the combination of the master and stochastic differential equations, we investigate in detail a continuous-variable entanglement of the twin beam generated by the coherent beat laser containing a parametric amplifier and coupled to thermal light of an external environment. The dipole-forbidden transition of the three-level atoms are coupled by the initial coherent superposition and classical pumping light emerging from the parametric oscillator. The atomic coherence induced by the classical pumping field and the initial coherent superposition induce a strong correlation between the two-mode radiation, which results in a high degree of the photon entanglement. In addition, the parametric amplifier enhances the achievable degree of entanglement of the two-mode fields. On the other hand, thermal light appears to degrade entanglement but a strong photon entanglement can be generated by managing the amount of thermal noise entering into the laser cavity through the output mirror.
In this paper, the analysis of the quantum properties of cavity light produced by a coherently dr... more In this paper, the analysis of the quantum properties of cavity light produced by a coherently driven nondegenerate three-level laser in a closed cavity and coupled to a two-mode vacuum reservoir, is presented. Normal ordering of the noise operators associated with the vacuum reservoir is considered. Applying the solutions of the equations of evolution for the expectation values of the atomic operators and the quantum Langavin equations for the cavity mode operators, the quadrature squeezing, entanglement amplification, and the normalized second-order correlation function of the cavity radiation are obtained. The three-level laser generates squeezed light under certain conditions, with maximum intracavity squeezing being 43% below the vacuum-state level. Moreover, it is found that the photon numbers of a two-mode light beams are correlated. PACS codes: 42.50.Dv, 42.50.Ar, 03.67.Mn
In this paper, the effect of a squeezed parameter and parametric amplifier on squeezing and entan... more In this paper, the effect of a squeezed parameter and parametric amplifier on squeezing and entanglement of a correlated emission laser is thoroughly analyzed. The combination of the master equation and stochastic differential equation is presented to study the quantum features of the light. Moreover, with the aid of the resulting solutions together with the correlation properties of noise operators, the quadrature squeezing and entanglement and the mean number of photon pairs of the cavity light are determined. It is found that a large amplitude of the classical driving radiation induces a strong correlation between the top and bottom states of three-level atoms to produce a high degree of squeezing and entanglement. Furthermore, the presence of parametric amplifier and squeezed parameter is found to enhance the degree of squeezing and entanglement of the cavity light.
the terms of the Creative Commons Attribution-Noncommercial 3.0 Unported License http://creativec... more the terms of the Creative Commons Attribution-Noncommercial 3.0 Unported License http://creativecommons.org/licenses/bync/3.0/), permitting all non commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. AbstractIn this paper, we investigated the steady-state analysis of the squeezing and statistical properties of the light generated by N two-level atoms available in a closed cavity pumped by a coherent light with the cavity coupled to a singele mode vacuum reservoir. Here we consider the noise operators associated with the vacuum reservoir in normal order. Applying the solutions of the equations of evolution for the expectation values of the atomic operators and the quantum Langavin equations for the cavity mode operators, we obtain the mean photon number, the photon number variance, and the quadrature squeezing. The three-level laser generates squeezed light under certain conditions, with maximum global squeezing being 43%. Moreo...
The von-Neumann entropy (VNE), usually expressed in terms of the density operator, is the mathema... more The von-Neumann entropy (VNE), usually expressed in terms of the density operator, is the mathematical tool to measure the degree of entanglement of a bi-partite system. Applying the solutions of the quantum Langevin equations, the anti-normally ordered characteristic function of the intra-cavity photons produced by a non-degenerate parametric oscillator could be calculated. With the help of the resulting characteristic function, the Q- function which is then used to calculate the entanglement of the intracavity photons using VNE is determined. Moreover, the photon number distribution, the mean photon number, the normalized second order correlation function, the intensity difference, and quadrature variance for the intra-cavity photons produced by a nondegenerate parametric oscillator coupled to a two-mode squeezed vacuum reservoir is determined. It was found that when the squeeze parameter increases the entanglement also increases. These show that the entropy entanglement has a dir...
Thin films of  phosphor have been successfully prepared by pulsed laser deposition using Nd-YAG l... more Thin films of  phosphor have been successfully prepared by pulsed laser deposition using Nd-YAG laser (266 nm, pulse duration of 10 ns, repetition rate of 2Hz) on a  (100) silicon substrate in vacuum environment and for different target to substrate distances. The X-ray diffraction (XRD) results show that the films crystallized in tetragonal polycrystalline phase of  (in agreement with JCPDS card No 27-0465). Theoretical predictions of the thickness profile have been presented using some experimental parameters used during deposition. Assuming ellipsoidal expansion of the plasma plume, the thickness profile of the films has been estimated from the solution of the gas dynamical equations for adiabatic expansion of the plasma plume in to vacuum. The results show strong forward direction of the plume and are in a good agreement with experimental results. Both theoretical and experimental results show the decrease in film thickness for relatively larger values of target to substrate dis...
We analyze a nondegenerate three-level cascade laser with an open cavity and coupled to a two-mod... more We analyze a nondegenerate three-level cascade laser with an open cavity and coupled to a two-mode thermal reservoir employing the stochastic differential equations for atomic operators associated with the normal ordering. Applying the large-time approximation scheme, we obtain the solutions for the corresponding equations of evolution of the expectation values of atomic operators. Furthermore, employing the resulting solutions, we studied the photon as well as cavity atomic-state entanglement amplification of the cavity radiation.
In this paper, employing the stochastic differential equations associated with the normal orderin... more In this paper, employing the stochastic differential equations associated with the normal ordering, the quantum properties of a nondegenerate three-level cascade laser with a parametric amplifier and coupled to a two-mode thermal reservoir are thoroughly analyzed. Particularly, the enhancement of squeezing and the amplification of photon entanglement of the two-mode cavity light are investigated. It is found that the two cavity modes are strongly entangled and the degree of entanglement is directly related to the two-mode squeezing. Despite the fact that the entanglement and squeezing decrease with the increment of the mean photon number of the thermal reservoir, strong amount of these nonclassical properties can be generated for a considerable amount of thermal noise with the help of the nonlinear crystal introduced into the laser cavity. Moreover, the squeezing and entanglement of the cavity radiation enhance with the rate of atomic injection.
The detailed analysis of the two-mode quadrature squeezing and statistical properties of light ge... more The detailed analysis of the two-mode quadrature squeezing and statistical properties of light generated by a nondegenerate three-level laser which has a parametric amplifier and coupled with a thermal reservoir is executed. The combination of the master equation and the stochastic differential equation is presented to study the nonclassical features of the light generated by the quantum system. Moreover, with the aid the resulting solutions together with the correlation properties of noise operators, we calculated the quadrature squeezing, entanglement, and mean number of photon pairs of the cavity light. It is found that the external small-amplitude driving radiation induces a strong correlation between the top and bottom states of three-level atoms to produce a high degree of squeezing. Moreover, the presence of a parametric amplifier is found to enhance the degree of squeezing of the cavity light. We have also established that an increase in the mean thermal photon number appear...
We analyse the entanglement of the light produced by a three-level laser whose cavity contains a ... more We analyse the entanglement of the light produced by a three-level laser whose cavity contains a parametric amplifier, with the cavity mode driven by the coherent light and coupled to a squeezed vacuum reservoir. Employing stochastic differential equations associated with the normal ordering resulted from the pertinent master equation, the quadrature variances and entanglement of the two-mode light are obtained and photon statistics of the two-light modes is discussed. It is found that the three-level laser generates squeezed light under certain conditions, with maximum intracavity squeezing being 89.7% below the coherent state level. We also show that the parametric amplifier enhances the mean photon number and photon number correlation.
We have analyzed the squeezing and statistical properties of the cavity light beam produced by a ... more We have analyzed the squeezing and statistical properties of the cavity light beam produced by a coherently driven degenerate three-level laser with a degenerate parametric amplifier (DPA) in an open cavity and coupled to a vacuum reservoir via a single-port mirror. We have carried out our analysis by putting the noise operators associated with the vacuum reservoir in normal order. Applying the solutions of the equations of evolution for the expectation values of the atomic operators and the quantum Langevin equation for the cavity mode operator, the mean photon number and the quadrature squeezing of the cavity light are calculated. And a large part of the mean photon number is confined in a relatively small frequency interval. Furthermore, we also obtain the antinormally ordered characteristic function defined in the Heisenberg picture. With the aid of the resulting characteristic function, we determine the function which is then used to calculate the photon number distribution.
Levofloxacin (LVF) and norfloxacin (NRF) are a group of fluoroquinolone antibiotics, broad spectr... more Levofloxacin (LVF) and norfloxacin (NRF) are a group of fluoroquinolone antibiotics, broad spectrum used to treat various infections caused by many bacterial species. The drugs contain functional groups which control the type and degree of interaction with different solvents. In this research, the ground and excited state dipole moments of LVF and NRF drugs were estimated using solvatochromic effects and computational work. The dipole moments were estimated from absorption and emission spectra in polar and nonpolar solvents using Bakhshiev’s, Kawski–Chamma–Viallet, Lippert–Mataga, and Reichardt models. The results indicated the emission spectra are more strongly affected by solvent polarity than the absorption spectra. The calculated excited state dipole moment is larger than that of the ground state, indicating that the probe compounds are significantly more polarized in the excited state than in the ground state. From computational work, the HOMO-LUMO energy band gap, the dipole m...
In this paper, the quantum properties of a two-level atom interaction with squeezed vacuum reserv... more In this paper, the quantum properties of a two-level atom interaction with squeezed vacuum reservoir is throughly analyzed. With the aid of the interaction Hamiltonian and the master equation, we obtain the time evolution of the expectation values of the atomic operators. Employing the steady-state solution of these equations, we calculate the power spectrum and the second-order correlation function for the interaction of two-level atom with squeezed vacuum reservoir. It is found that the half width of the power spectrum of the light increases with the squeeze parameter, . Furthermore, in the absence of decay constant and interaction time, it enhances the probability for the atom to be in the upper level.
The role of phase fluctuation on the quantum and statistical features of the two-mode radiation p... more The role of phase fluctuation on the quantum and statistical features of the two-mode radiation produced by a correlated emission laser which is externally injected with squeezed radiation is discussed. The considered atoms are prepared in the ground and excited states with equal probabilities before being injected into the laser cavity, and an external coherent field generates the atomic coherence that leads to the non-classical features in the quantum system. A non-degenerate parametric amplifier is also introduced into the laser cavity which is coupled to a two-mode squeezed environment. It is found that the quantum and statistical properties are very sensitive to and highly altered by the phase fluctuation when the strength of the external coherent field is weak. On the contrary, the external coherent field entirely overcomes the influence of phase fluctuation for the amplitude of the external coherent field that lies in the strong pumping regime so that the strength of squeezin...
The concept of relativistic multipole expansion is applied to determine the multipole moments of ... more The concept of relativistic multipole expansion is applied to determine the multipole moments of the electric potential of a charged system moving at constant velocity with respect to a stationary observer. A system of discrete point charges and a charged plate of uniform surface charge density were considered for analysis. For relativistic considerations, two reference frames: namely S and SËŠ were chosen. SËŠ, which contains the charged system, is moving with constant velocity relative to frame S, to which stationary observer is attached. For easy comparison, both multipole expansions are expressed in terms of the coordinates of the SËŠ frame. The two observers in S and SËŠ, in general, calculate different expressions of multipole expansion for the same charged system because of Lorentz contraction effect. The multipole terms of the potential evaluated by the observer in S is time dependent. This shows that there are also magnetic effects, which are not observed by an observer in SËŠ.
Applying the combination of the master and stochastic differential equations, we investigate in d... more Applying the combination of the master and stochastic differential equations, we investigate in detail a continuous-variable entanglement of the twin beam generated by the coherent beat laser containing a parametric amplifier and coupled to thermal light of an external environment. The dipole-forbidden transition of the three-level atoms are coupled by the initial coherent superposition and classical pumping light emerging from the parametric oscillator. The atomic coherence induced by the classical pumping field and the initial coherent superposition induce a strong correlation between the two-mode radiation, which results in a high degree of the photon entanglement. In addition, the parametric amplifier enhances the achievable degree of entanglement of the two-mode fields. On the other hand, thermal light appears to degrade entanglement but a strong photon entanglement can be generated by managing the amount of thermal noise entering into the laser cavity through the output mirror.
In this paper, the analysis of the quantum properties of cavity light produced by a coherently dr... more In this paper, the analysis of the quantum properties of cavity light produced by a coherently driven nondegenerate three-level laser in a closed cavity and coupled to a two-mode vacuum reservoir, is presented. Normal ordering of the noise operators associated with the vacuum reservoir is considered. Applying the solutions of the equations of evolution for the expectation values of the atomic operators and the quantum Langavin equations for the cavity mode operators, the quadrature squeezing, entanglement amplification, and the normalized second-order correlation function of the cavity radiation are obtained. The three-level laser generates squeezed light under certain conditions, with maximum intracavity squeezing being 43% below the vacuum-state level. Moreover, it is found that the photon numbers of a two-mode light beams are correlated. PACS codes: 42.50.Dv, 42.50.Ar, 03.67.Mn
In this paper, the effect of a squeezed parameter and parametric amplifier on squeezing and entan... more In this paper, the effect of a squeezed parameter and parametric amplifier on squeezing and entanglement of a correlated emission laser is thoroughly analyzed. The combination of the master equation and stochastic differential equation is presented to study the quantum features of the light. Moreover, with the aid of the resulting solutions together with the correlation properties of noise operators, the quadrature squeezing and entanglement and the mean number of photon pairs of the cavity light are determined. It is found that a large amplitude of the classical driving radiation induces a strong correlation between the top and bottom states of three-level atoms to produce a high degree of squeezing and entanglement. Furthermore, the presence of parametric amplifier and squeezed parameter is found to enhance the degree of squeezing and entanglement of the cavity light.
the terms of the Creative Commons Attribution-Noncommercial 3.0 Unported License http://creativec... more the terms of the Creative Commons Attribution-Noncommercial 3.0 Unported License http://creativecommons.org/licenses/bync/3.0/), permitting all non commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. AbstractIn this paper, we investigated the steady-state analysis of the squeezing and statistical properties of the light generated by N two-level atoms available in a closed cavity pumped by a coherent light with the cavity coupled to a singele mode vacuum reservoir. Here we consider the noise operators associated with the vacuum reservoir in normal order. Applying the solutions of the equations of evolution for the expectation values of the atomic operators and the quantum Langavin equations for the cavity mode operators, we obtain the mean photon number, the photon number variance, and the quadrature squeezing. The three-level laser generates squeezed light under certain conditions, with maximum global squeezing being 43%. Moreo...
The von-Neumann entropy (VNE), usually expressed in terms of the density operator, is the mathema... more The von-Neumann entropy (VNE), usually expressed in terms of the density operator, is the mathematical tool to measure the degree of entanglement of a bi-partite system. Applying the solutions of the quantum Langevin equations, the anti-normally ordered characteristic function of the intra-cavity photons produced by a non-degenerate parametric oscillator could be calculated. With the help of the resulting characteristic function, the Q- function which is then used to calculate the entanglement of the intracavity photons using VNE is determined. Moreover, the photon number distribution, the mean photon number, the normalized second order correlation function, the intensity difference, and quadrature variance for the intra-cavity photons produced by a nondegenerate parametric oscillator coupled to a two-mode squeezed vacuum reservoir is determined. It was found that when the squeeze parameter increases the entanglement also increases. These show that the entropy entanglement has a dir...
Thin films of  phosphor have been successfully prepared by pulsed laser deposition using Nd-YAG l... more Thin films of  phosphor have been successfully prepared by pulsed laser deposition using Nd-YAG laser (266 nm, pulse duration of 10 ns, repetition rate of 2Hz) on a  (100) silicon substrate in vacuum environment and for different target to substrate distances. The X-ray diffraction (XRD) results show that the films crystallized in tetragonal polycrystalline phase of  (in agreement with JCPDS card No 27-0465). Theoretical predictions of the thickness profile have been presented using some experimental parameters used during deposition. Assuming ellipsoidal expansion of the plasma plume, the thickness profile of the films has been estimated from the solution of the gas dynamical equations for adiabatic expansion of the plasma plume in to vacuum. The results show strong forward direction of the plume and are in a good agreement with experimental results. Both theoretical and experimental results show the decrease in film thickness for relatively larger values of target to substrate dis...
We analyze a nondegenerate three-level cascade laser with an open cavity and coupled to a two-mod... more We analyze a nondegenerate three-level cascade laser with an open cavity and coupled to a two-mode thermal reservoir employing the stochastic differential equations for atomic operators associated with the normal ordering. Applying the large-time approximation scheme, we obtain the solutions for the corresponding equations of evolution of the expectation values of atomic operators. Furthermore, employing the resulting solutions, we studied the photon as well as cavity atomic-state entanglement amplification of the cavity radiation.
In this paper, employing the stochastic differential equations associated with the normal orderin... more In this paper, employing the stochastic differential equations associated with the normal ordering, the quantum properties of a nondegenerate three-level cascade laser with a parametric amplifier and coupled to a two-mode thermal reservoir are thoroughly analyzed. Particularly, the enhancement of squeezing and the amplification of photon entanglement of the two-mode cavity light are investigated. It is found that the two cavity modes are strongly entangled and the degree of entanglement is directly related to the two-mode squeezing. Despite the fact that the entanglement and squeezing decrease with the increment of the mean photon number of the thermal reservoir, strong amount of these nonclassical properties can be generated for a considerable amount of thermal noise with the help of the nonlinear crystal introduced into the laser cavity. Moreover, the squeezing and entanglement of the cavity radiation enhance with the rate of atomic injection.
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