In this paper the motion of electron in a miniband of a SEMICONDUCTOR superlattice (SSL) under the influence of external electric and magnetic fields is investigated. The electric field is applied in a direction perpendicular to the layers of the SEMICONDUCTOR superlattice, and the magnetic field is applied in different direction Numerical calculations show conditions led to the possibility of chaotic behaviors.

The present contribution is devoted to the production of the Ni-Bi-Se thin films widely used in the field of electronics, electrotechnology, and computer technology. During the process, at first, the Bi-Se compound has been formed on the nickel electrode by electrochemical method, and then by thermal treatment of this compound at 673K, ternary compound Ni3Bi2Se2 has been obtained. The results show that as the concentration of bismuth is increasing, its amount in deposited films increases regularly. The formation of the Ni3Bi2Se2 compound was also confirmed by XRD results. The photochemical properties of the obtained compounds were investigated in the dark and light, constant current of 100 nA for 0-600 seconds. With the illumination of the dark samples, the potential shifts from a positive side to a negative side, this decrease indicates that obtained thin films are not only photosensitive, also have n-type conductivity.

In this paper, series expansion is used to solve Liouville equation and two terms of the series are derived. Using the solution, an effective classical potential is defined which contains quantum effects. It is shown for two classical potential Is, step potential and barrier potential, that in the effective potential, discontinuities are smoothed. Furthermore, it is demonstrated that the difference between the classical potential, with slow changes over position, and its effective potential is small.

Persistent photoconductivity (ppc) has been investigated in detail in a bulk CdTe (Sb) SEMICONDUCTOR. The relaxation of ppc in CdTe (Sb) is found to follow a power_law, Ippc (t)=t –a, in temperature region 110K< T<295 K, The parameter a as a function of temperature is obtaind.However, the ppc is observed only above 90K, that is contrast to previous reported results on most materials which exhibit PPC effects predominantly at low temperatures. Apossible mechanism is the presence of random local potential fluctuations in the sample, which strongly influence the carrier transport properties. Such fluctuations could be induced either by the compositional fluctuations or the impurity potential.

We investigate the deposition temperature, pH and deposition time that govern evolution of the NANOPARTICLE shape, size and density of ZnSe NANOPARTICLE arrays. The NANOPARTICLE arrays were grown on glass substrate using a facile chemical bath deposition method. The samples were also characterized by absorbance spectra for energy band gap determination and scanning electron microscopy. In comparison to other similar works, our method is simple, low cost and can be easily controlled. We find that temperature helps to tailoring the NANOPARTICLE shape and has a critical role in comparison with other parameters such as pH and deposition time.

A simple and low temperature method is proposed for preparation of CdS NANOPARTICLEs in presence of 1-ethyl-3-methylimidazolium ethyl sulfate, [EMIM] [EtSO4], a room-temperature ionic liquid (RTIL). The powder X-ray diffraction (XRD) studies display that the products are excellently crystallized in the form of cubic structure and size of the nanparticles prepared in presence of the RTIL is smaller than that prepared in water. Energy dispersive X-ray spectroscopy (EDX) investigations reveal that the products are very pure and nearly stoichiometric. The results obtained by scanning electron microscopy (SEM) demonstrate that the CdS NANOPARTICLEs prepared in presence of the RTIL have lower tendency for aggregation relative to the prepared sample in water. Diffuse reflectance spectra (DRS) of the product prepared in the neat RTIL, shows 1.52 eV blue shift relative to bulk CdS, which can be attributed to quantum confinement effect of the CdS NANOPARTICLEs. A possible formation mechanism for CdS NANOPARTICLEs in presence of the RTIL is presented. Photocatalytic activity of the CdS NANOPARTICLEs towards photodegradation of methylene blue (MB) using UV and visible lights was performed. The results demonstrate that observed first-order rate constant for photodegradation of MB on CdS NANOPARTICLEs prepared in the neat RTIL are about 20 and 6 times greater than the prepared sample in water using visible and UV lights, respectively .

In this work, we study electronic transport properties of a quasi-one dimensional pure semi-conducting Zigzag Carbon Nanotube (CNT) attached to semi-infinite clean metallic Zigzag CNT leads, taking into account the influence of topological defect in junctions. This structure may behave like a field effect transistor. The calculations are based on the tight-binding model and Green’s function method, in which the local density of states (LDOS) in the metallic section to semi-conducting section, and muli-channel conductance of the system are calculated in the coherent and linear response regime, numerically. Also we have introduced a circuit model for the system and investigated its current. The theoretical results obtained, can be a base, for developments in designing nano-electronic devices.