International Journal of Modern Physics B

We review recent experimental studies on polarized atomic Fermi gases. The particular focus is on our own experiments of strongly interacting two-component Fermi gases with imbalanced populations. The real-space density distributions reveal a superfluid/normal phase separation at very low temperatures, accompanied by deformation of evenly paired core; at higher temperatures, a partially polarized phase is observed.

In this letter, the influence of an applied electric field on a periodic structure composed of alternating layers of DPS (Double Positive index of refraction) and DNG (Double Negative index of refraction) has been studied. We present theoretical and numerical results of our investigation of the reflection spectra of the visible waves on this structure in the presence of an electric field which will cause redistribution of charges and will modify the index of refraction of materials and enable us to control the phase and/or intensity of propagating electromagnetic waves.

To investigate the effect of TiN coating on the fatigue strength of high-strength steel, four-point bending fatigue tests were carried out for martensitic stainless steel with TiN film coated using arc ion plating (AIP) method. A 2-μm-thick TiN film was deposited onto the substrate surface under bias voltage of four kinds: V_B = 0, -60, -160 and -260 V. For V_B = 0, -160 V and -260 V, the fatigue limit increased. The highest fatigue limit of σ_max = 900 MPa was obtained for V_B = -160 V. But some samples for V_B = -260 V showed the decrease of fatigue limit due to film delamination during the fatigue test. For V_B = -60 V, the fatigue limit was unchanged by coating. As a result of a coating property analysis, the following conclusions were obtained. Fatigue crack propagation was almost independent of the bias voltage. Fatigue crack initiated from the subsurface in the substrate and the crack initiation behavior depended on the film property of the adhesion, residual stress, elastic modulus, and the film's hardness depended on the bias voltage especially for low fatigue stress level.

Nanocrystalline samples of Zn_1-xMn_xO (x = 0.0, 0.01, 0.02, 0.1 and 0.2) were synthesized by solid state reaction and characterized by X-ray diffraction and electron paramagnetic resonance (EPR) at room temperature. EPR studies showed an evidence of ferromagnetism above room temperature.

We present a scheme that can realize quantum cloning of an unknown two-particle entangled state and its orthogonal-complement state with assistance offered by a state preparer, via entangled cluster state as quantum channel. The first stage of the scheme requires usual teleportation via a maximally four-particle entangled cluster state as quantum channel. In the second stage of the scheme, with the assistance (through a two-particle projective measurement) of the preparer, the perfect copies and complement copies of an unknown two-particle entangled state can be obtained. We also put forward a scheme for the teleportation by using nonmaximally entangled quantum channel. The clones and complement clones of unknown state can be produced with certain probability in the latter scheme.

We investigate the evolution of the atomic quantum entropy and the atom–field entanglement in a system of a Λ-configuration three-level atom interacting with a single-mode field with additional forms of nonlinearities of both the field and the intensity-dependent atom–field coupling. With the derivation of the unitary operator within the frame of the dressed state and the exact results for the state of the system, we perform a careful investigation of the temporal evolution of the entropy. A factorization of the initial density operator is assumed, considering the field to be initially in a squeezed coherent or binomial state. The effects of the mean photon number, detuning, Kerr-like medium, and the intensity-dependent coupling functional on the entropy are analyzed.

Phenomena of electron, neutron, atomic, and molecular diffraction have been studied in many experiments, and these experiments have been explained by some theoretical works. We study neutron single and double-slit diffraction with a new quantum mechanical approach. The calculation results are compared with the experimental data obtained with cold neutrons.

In this paper, we apply the variational iteration method using Adomian's polynomials (VIMAP) to investigate propagating traveling solitary wave solutions of seventh-order generalized KdV (SOG-KdV) equations, which play a very important role in mathematical physics, engineering, and applied sciences. The suggested algorithm is quite efficient and is practically well suited for use in these problems. The proposed iterative scheme finds the solution without any discretization, perturbation, linearization, or restrictive assumptions and is formulated by the elegant coupling of variational iteration method and Adomian's polynomials.

Radio-frequency (HF) quasi-potential Φ in the field of the space charge region of contact of a metal–semiconductor is explored. At the frequency, ω, greater frequency plasma fluctuations ω₀ HF quasi-potential is positive, but at frequencies ω < ω₀ quasi-potential Ph is negative. VAC and Schottky barrier with provision for HF quasi-potential are calculated. It is shown that HF gives an essential contribution on EMF hot carriers when frequency of wave is less in electronic gas fluctuations in layer potential barrier.

The quantization of a mesoscopic transmission line in accordance with the discreteness of electric charges is proposed under the Born–Von-Karmann periodic boundary condition. The finite-difference Schrödinger equation of the circuit has been obtained in charge representation, and the Schrödinger equation is transformed into Mathieu equation in current representation. The wavefunction and energy spectrum can be solved by adopting the canonical transformation and unitary transformation method. Our results indicate that in the transmission line, quantum fluctuation of currents, which also have distributed properties, are related to both the circuit parameters and the positions and the mode of signals.

Composites of polyaniline with synthesized nanostructured titania (TiO₂) and polyaniline with commercial TiO₂ have been in situ synthesized by oxidative chemical polymerization method. Sulfuric acid was used as dopant during the polymerization process. Sol-gel precipitates of nanostructured titania were synthesized by hydrolyzing the mixture of titanium chloride (TiCl₃) and colloidal transparent solution of starch. Composite materials were subjected for comparison to spectroscopic and X-ray diffraction analysis. Strong coupling/interaction of titania with the imine nitrogen in polyaniline confirmed by FTIR spectral analysis. XRD shows the composite of synthesized titania with polyaniline have broaden peak as compared to that of commercial titania with polyaniline indicating particle size in the range of nanometer scale which is supported by 40 nm particle size of the synthesized titania from TEM picture. Increase in conductivity with increasing temperature was observed in both the composite materials.

The numerical results of a set of nonlinear equations for a modulation-doped GaAs/AlGaAs heterostructure under external fields are presented. For pure dc bias at a fixed magnetic field, we observe the self-sustained oscillations due to the traveling high electric field domain in the system. Varying the magnetic field, the width of the domain and the oscillation amplitude will be changed. By imposing the microwave irradiation, the system shows frequency locking, quasiperiodicity, and chaos depending on the amplitude and the frequency of the microwave. It is shown that these interesting oscillations are connected with the high electric field domains.