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We have researched the performance of Photonic Crystals(PCs), the magnetic material of which is SiO2/ZrO2 matrix doped with CoFe2O4 magnetic nanoparticles that has a promising future to overcome the problem of integration of magneto-optical isolators(MOIs). The above-mentioned magnetic material are obtained by the sol-gel processing can be used to prepare high optical quality magnetic layers of MOIs that are based on Magnetic Photonic Crystals (MPCs) structure. At wavelength 1550nm, we used the Transfer Matrix Method(TMM) to calculate the transmittance T, Faraday rotation angle θ F and ellipticity ψ F .

By using the method of eigenvectors, the atomic populations and emission spectrum are investigated in a system that consists of a cascade three-level atom resonantly interacting with a single-mode field in a Kerr-like medium. The atom and the field are assumed to be initially in the upper atomic state and the Fock state, respectively. Results for models with intensity-dependent coupling and with intensity-independent coupling are compared. It is found that both population dynamics and emission spectrum show no indications of atom-field decoupling in the strong field limit if the intensity-dependent coupling is taken into account.

We investigate the evolution of a quantum system described by the Jaynes–Cummings model with an arbitrary form of intensity-dependent coupling by displaying the linear entropies of the atom, field and atom–field system in the large detuning approximation. The cavity field is assumed to be coupled to a reservoir with a phase-damping coupling. The effects of cavity phase damping on the entanglement and coherence loss of such a system are studied.

The position- and momentum-entopic squeezing properties of the optical field in the system of a nearly degenerate three-level atom interacting with a single-mode field are investigated. Calculation results indicate that when the field is initially in the vacuum state, it may lead to squeezing of the position entropy or the momentum entropy of the field if the atom is prepared properly. The effects of initial atomic state and the splitting of the excited levels of the atom on field entropies are discussed in this case. When the initial field is in a coherent state, we find that position-entropy squeezing of the field is present even if the atom is prepared in the ground state. By comparing the variance squeezing and entropy squeezing of the field we confirm that entropy is more sensitive than variance in measuring quantum fluctuations.

Conversional NMO and stack method is based on the assumption that the surface and subsurface are all horizontal. But most of the cases, this assumption can't be satisfied. So, velocity estimated by this method is not accurate sufficiently for other attribute analysis. Ellipse evolving common reflection point method is an innovative stack method. It implements tangent intervening and stacking by evolving seismic signals to isochrones along elliptic trajectory under some velocity distribution to obtain real zero-offset section. This paper, introduces this method into velocity analysis. It introduces detailed principle of velocity estimation for the homogeneous and heterogeneous media respectively. It reasons rigorously out that estimated velocity is the true CRP stack velocity with practical geological meaning. Hanging together with theoretical models computing and practical seismic data processing, makes sure that we can use ellipse evolving CRP velocity analysis method to estimate more accurate CRP stack velocity and other velocities of complex geology sections, and to detect interval velocity anomaly more clearly. It is a good assistant method of reservoir prediction and oil and gas detection.

A full quantum theory is adopted to derive the differential equations satisfied by the state of a system that is composed of an electron tunneling-coupled quantum-dot molecule interacting with a single-mode radiation field. The phase of the field is calculated by the Pegg-Barnett quantum phase formalism under the initial condition of a coherent-state field and the tunneling excited state or ground state for the quantum-dot molecule. Phase distribution and fluctuation of the field are analyzed, the influence of interaction between phonons and the quantum-dot molecule on the Pegg-Barnett quantum phase is investigated, and the phase distribution is compared with the Husimi phase distribution of the field. Results indicate that temperature can have a marked impact on the phase evolution. The existence of phonons suppresses the field phase distribution and fluctuation in the case when the quantum dot molecule is initially in the tunneling-excited state, while it enhances the diffusion and fluctuation of the field phase in the case when the quantum dot molecule is initially in the ground state. The Husimi phase distribution and the Pegg-Barnett phase distribution agree with each other fairly well in our study.

We investigate the dynamics of a quantized vortex in a trapped superfluid Fermi gas near the unitarity limit. By taking a trial wave function for the order-parameter of a condensate in a rotating axisymmetric trap confinement and using a time-dependent variational analysis we obtain the equations of motion and their solutions for anomalous mode. The results show that the critical rotating frequency of the trap increases when the system ranges from the left to the right side of the unitarity limit, while the period of the vortex decreases in this regime.

Under the assumption of orthogonal electrical dipole moments of a cascade three-level atom with equally spaced energy levels, the full quantum theory is applied to study the emission spectrum of the atom interacting resonantly with a single-mode electromagnetic field in an ideal cavity. Spectral calculations for both the intensity-dependent and intensity-independent couplings are performed and the spectra in the cases of orthogonal dipole moments and parallel dipole moments are compared. It is found that some spectral lines disappear for the atom with parallel dipoles due to destructive interference leading to fewer lines compared with the spectrum of the atom with orthogonal dipole moments.

The evolution of the field (atomic) entropy in a system of a quasi_Λ_type fourlevel atom interacting with an uncoupled two_mode coherent field is investigated. The effects of initial atomic state, the initial mean photon number and the splitting of the atomic energy levels on the entropy are discussed. The system reduces to that of a twolevel or threelevel atom interacting with a singlemode coherent field in special cases.

The time evolution of entanglement and disentanglement between a Λ-type three-l evel atom and a single-mode field initially in the number state in an ideal cavi ty are investigated by considering von Neumann entropy of the optical field. Res ults indicate that entanglement of the system displays periodicity; the maximal degree of entanglement depends on the initial atomic state, the initial photon n umber and the ratio of detuning to the coupling constant, while the number of ti mes for maximal entanglement and disentanglement in a period is independent of t he initial photon number. The initial relative phase between the two lower state s have effects on the time evolution of field entropy, while the initial relativ e phases between the excited state and the ground states of the atom does not.

The electrical resistivity of the heavy-fer mion alloy system is calculated through the Yoshimori-Kasai model with the application of the slave-boson technique. The residual resistivity of the system is found in the mean-field approximation by using the CPA method-The low-temperature resistivity maximum in the concentrated alloy is aslo obtained as the Gaussian fluctuation of the slave-boson field is included.

The coherent band states of the infinite lattice Anderson model with introducing a small dispersion into the -band are derived in the framework of the slave-boson mean field theory. The temperature dependences of the pseudogap in - and conduction electrons' density of states near the Fermi level are calculated self-consistently. The calculation is applied to discuss the low temperature properties of the heavy-electron metals. The results show that with decreasing temperature the coefficient of the thermoelectric power changes sign below the Kondo temperature , and an additional positive peak will appear at the rather lower temperatures, which are in agreement with the experimental results in .

In this article, a theory describing the normal state of the heavy-fermion alloys has been proposed based on the Yoshimorikasai model in the framework of slave-boson mean field theory by using the CPA method. The density of states (DOS) and its concentration dependences for the conduction electrons and strong correlated f-electrons in the heavy-fermion alloys are calculated self-consistently. The results we obtained not only reveal the process of the pseudo-gap formation in the DOS, but also give a reasonable explanation of the low temperature coherence effects in specific heat and thermoelectric power for the heavy-fermion alloys.