Studying a new kind of multiphoton resonances by using symmetric laser fields
Mostafa Karami, Parsa Zamani, Khadijeh Karami, Firoozeh Jamshidi
Abstract In this paper the occurrence of interference resonances and their different behavior at even or odd multiples of photon are studied by using symmetric laser fields that are strongly coupled with two energy levels of a four-level system. For doing this work, a model is presented based on crossing points of levels where transitions are created. At first multiphoton resonances in the two-level and three-level systems are investigeted briefly and compared with each other through calculating of interference phase, then the strong dephasing regime for a four-level system is introduced and the levels are become time-dependent, in this way, the transition rates of second order and fourth order that have resonant features for integer n (photon number) are calculated. The calculations display asymmetry of resonances at multiples of even or odd is insensitive to fluctuations of the strongly driven levels, and survives into the strong dephasing regime. We investigate the detuning dependence of current steady-state and its complete agreement with the experiments which are done based on calculating current in spin-blockaded conditions via the levels modeling a double quantum dot and by using numerical simulation. Finally, we show the obtained results have the main features of the experimental data.
Investigation of the amplitude modulation of the nonlinear waves in laser-plasma interaction with Tsallis distribution function for electrons
Alireza Abdikian, Mohamadreza Mohebifar, Sharare Raj
Abstract In this paper, the electromagnetic solitary wave due to the interaction of laser pulse and plasma media was studied by using a system of the nonlinear electron hydrodynamics and Maxwell’s equations. The Tsallis distribution function is assumed for the electron particles. By implementing the multiple scales technique, the nonlinear Schrodinger equation govern on the vector potential was derived. Analytically, the effects of nonextensive and nonthermal parameters on the condition of the modulation instability and existence of the types of envelope modes (bright and dark), were discussed in detail. Finally, the regions of the modulation stability and instability were studied numerically by plotting some figures.
Investigation of the Effects of Prismatic Against the Flat Cover Window for Solar Collectors Using a 3D Ray-tracing Matrix Method
Afzal Raghavi
Abstract A 3D ray-tracing matrix method is employed for studying the effects of directional distribution of radiation sources on transmission coefficient of a transparent plate with a prismatic ridged surface. An optimized configuration is suggested for using a prismatic plate as the glazing cover of a solar collector. Promising application of the resulting properties is suggested for optimizing the efficiency of solar collectors, when their routine glassy window is replaced by a prismatic one.
Radial distribution function within the third version of the Tsallis statistical mechanics
Mohammad Amin Tabatabaei Bafghi, Mohammad Kamalvand, Ali Morsali
Abstract Nowadays, a variety of physical systems have been known whose thermodynamic behavior, due to non-extensive effects, is not explicable by the common Boltzmann-Gibbs (BG) statistical mechanics. Thus, the correction of the BG entropy seems to be essential. In this regard, an efficient extension has been promoted by Tsallis, which is based on a generalized entropic form. In this study, a new equation is derived for the Radial Distribution Function (RDF) by taking into account the third version of the Tsallis statistics. To this end, probability distribution function is applied within the third version of the Tsallis statistics. Moreover, a closed formula is proposed for RDF. The momenta and the coordinates are independent in this equation. The effect of the non-extensivity parameter, q, on the RDF of a Lennard-Jones fluid, was investigated. At low densities, the results of the numerical calculations performed for RDF indicated that, the correlation increases with an increase in the values of q. Increase of the non-extensivity parameter and that of has similar effects.
The effect of power law noise on the random deposition and random deposition with surface relaxation models
sakineh hosseinabadi, zeinab karimi afosi, fatemeh tavakoli, nastaran mohajeri, Amir Ali Masoudi
Abstract In this study, the effect of correlated and uncorrelated power law noise on the random deposition and random deposition with surface relaxation models is investigated. In simple forms of these models with white noise, the particles randomly select a site for deposition; however, in this study, these models are simulated with a correlated power noise where the distance between deposition sites follows a power law relation as δx = int [r ^ (- 1 / (۲ρ))], and with uncorrelated power noise where the particles size is determined via the relation P (l) ~ l ^ (- (μ + 1)). In the above relations, r is a random number with a uniform distribution in the interval (0, 1), ρ is the correlation intensity and µ is the noise exponent. The results show that the scaling of these models is completely different and multi-fractal features are observed in the power law noises. The growth exponent for the random deposition model with various values of correlation intensity ρ is a constant value equal to β = 0.5 ± 0.02, whereas for the random deposition with surface relaxation model, this exponent enhances from β = 0.25 ± 0.02 in ρ = 0 (equivalent to simple version of this model with white noise) to β = 0.5 ± 0.02 in ρ = 1 and remains constant. According to the results, uncorrelated power law noise leads to a step function enhancement of roughness width at different growth times. The fractal analysis performed by the Multi-fractal detrended fluctuation analysis(MFDFA) method illustrates the multi-fractal behavior of the simulated rough surfaces.
Multihop quantum teleportation of N-qubit state by using composite of GHZ-EPR states
Negin Fatahi
Abstract The multihop teleportation is a useful scheme for quantum teleportation in long-distance, that there is no direct entanglement between a source node and a destination node. In this paper, multihop teleportation of single-qubit, two-qubit, and N-qubit states are presented by using the composition of the GHZ state and EPR state as a shared quantum channel between two adjacent nodes. In this scheme, the source node and intermediate nodes can make measurements simultaneously and send the measurement results to the destination node in parallelism, so that the transmission speed increases compared with the hop-by-hop transmission. Finally, the efficiency of this method is calculated. This scheme is suitable for transferring information in communication networks.
Design and Simulation of a Sensor based on Plasmonic Bragg reflector
Mohammad Vahedi, Mojtaba Moradkhani
Abstract In this paper, a plasmonic refractive index sensor is designed based on a Metal-Insulator-Metal waveguide coupled to a bragg reflector side-coupled to a rectangular cavity. A 2D-FDTD method is used to simulate the results. Results show that a maximum of 1320 nm/RIU for sensitivity and 45.5 RIU-1 for figure-of-merit could be obtained which shows the applicability of the sensor for accurate and compact sensing applications.
