scholarly journals Model of stationary migration of free and hopping via acceptors holes in a crystalline semiconductor

Author(s):  
N. A. Poklonski ◽  
A. N. Dzeraviaha ◽  
S. A. Vyrko

In the diffusion-drift approximation, we have constructed a phenomenological theory of the coexisting migration of v-band holes and holes by means of hopping from hydrogen-like acceptors in the charge state (0) to acceptors in the charge state (−1). A p-type crystalline semiconductor is considered at a constant temperature, to which an external stationary electric field is applied. In the linear approximation, analytical expressions for the screening length of the static electric field and the length of the diffusion of v-band holes and the holes quasilocalized on acceptors are obtained for the first time. The presented relations, as special cases, contain well-known expressions. It is shown that the hopping migration of holes via acceptors leads to a decrease in the screening length and in the diffusion length.

Author(s):  
Nikolai A. Poklonski ◽  
Aliaksandr N. Dzeraviaha ◽  
Sergey A. Vyrko ◽  
Aliaksandr I. Kavaleu

The study of semiconductor materials with point radiation defects of the crystal structure in three charge states (–1), (0), (+1) is important for determining the conditions of their radiation resistance under the influence of gamma rays, fast electrons, etc. Such defects are self-sufficient to ensure electrical neutrality of the material under conditions of ionization equilibrium, that issue determines the radiation resistance of materials. In silicon and diamond crystals, such irradiation-induced defects during their accumulation stabilize the Fermi level in the vicinity of one third of the band gap from the top of the valence band. The purpose of the work is an analytical description of the stationary hopping electron transfer in a semiconductor, taking into account the joint migration of both the single electrons and the pairs of electrons over these triple-charged defects. A crystalline semiconductor is considered as a matrix containing immobile point defects of one sort in the prevailing concentration. For the first time in the drift-diffusion approximation, a phenomenological theory is constructed of coexisting migration of both the single electrons (transitions from the charge state (–1) to state (0) and from the state (0) to state (+1)), and the electron pairs (transitions from the state (–1) to state (+1)) by means of their hopping between such defects when an external stationary electric field is applied to the semiconductor. In the linear approximation, analytical expressions are obtained for the screening length of a static electric field and the length of the hopping diffusion of electrons migrating via such defects. It is shown that the additional contribution of the hopping transport of electron pairs leads to a decrease in the screening length and also changes the diffusion length.


2018 ◽  
Vol 63 (12) ◽  
pp. 1109 ◽  
Author(s):  
Kh. A. Gasanov ◽  
J. I. Guseinov ◽  
I. I. Abbasov ◽  
F. I. Mamedov ◽  
D. J. Askerov

The spatial and time dispersions of the dielectric permittivity of an electron gas in quasi-two-dimensional quantum nanostructures are studied. The screening of the charge-carrier scattering potential in a quantum-confined film with a modified P¨oschel–Teller potential is considered for the first time. Analytical expressions for the dielectric permittivity are obtained.


Author(s):  
А.И. Грачев

In the paper the concept of conductive particle rotation in DC electric field with including the Lorentz force providing generation of electric dipole moment of the particle is for the first time discussed. Some models of the torque transfer to spherical and cylindrical particles based on of the Hall effect at usual geometry and with additional electric field application and also in the case of implementation of the photoelectromagnetic effect are presented.


2002 ◽  
Vol 57 (6-7) ◽  
pp. 586-590 ◽  
Author(s):  
W. Tröger ◽  
M. Dietrich ◽  
J. P. Araujo ◽  
J. G. Correia ◽  
H. Haas

For the first time the nuclear probe 204mPb was produced at the on-line isotope separator ISOLDE at CERN and used for time differential perturbed angular correlation experiments. The electric field gradient of 204mPb at room temperature in Cd metal was determined to be = 19(1) 1021 V/m2. Ab initio-calculations of the electric field gradient for the impurities Pt to Bi in cadmium were performed with the full-potential linearized augmented plane waves code WIEN97 to interpret this result. For Au, Hg and Pb, where experimental results are now available, these agree with the calculations within 10 %.


Author(s):  
Yury V. LISAKOV ◽  
Olga V. LAPSHINOVA ◽  
Nikolay M. PUSHKIN ◽  
Viktor P. KONOSHENKO ◽  
Nikolay V. MATVEEV ◽  
...  

The paper presents the results of analysis of electrical measurements performed in the space experiment "Impulse (stage 1)" on the Service module of the ISS RS. This experiment investigated the effects of the interaction of the charged component of the ionosphere to the surface of large KA, which is the ISS. This paper analyses the measurement of quasi-stationary electric field and current leakage, was, respectively, sensors of the vibration type and flat probes from the Complex control electrophysical parameters (CCEP), developed by SPJ MT. To study the dependence of measurements from the ionosphere flow direction to the surface of the ISS RS was installed two sets of sensors with the direction of the angle of "visibility" in the Nadir (towards the Earth) and to "satellite footprint " (against the velocity vector of the ISS). Carried out analysis of common regularities measurements depending on the sun-shadow environment on orbit ISS motions and depending on current geophysical dynamics of the ionosphere. Massive the measurements including more than 170 telemetric sessions were analyzed. More than 11000 hours of measurements current of leakage (or runoff current) and measurements of quasi-stationary electric field with discretization 1s and UT binding to each point were analysed. The data measurements, geophysical and orbital data were collected in an electronic album. It is shown that experimental data correlate with the crossing time of the ISS boundaries known geophysical structures: the noon Meridian, the Main ionospheric failure (MIF), the boundaries diffuse intrusion (BDI), the Equatorial Geomagnetic anomaly (EA). In this regard, despite the specificity of the ISS (the spacecraft super big sizes, the most complex spatial configuration) similar measurements, nevertheless, are quite suitable for monitoring researches of some features of an ionosphere at the level of F2 layer with a temporary scale from 1s and can be used for more detailed study of the geophysical structures and related effects in the ionosphere. In addition, the results obtained can be used for the analysis of disturbances of electromagnetic conditions near the surface of the ISS RS, for monitoring potential and currents of leakage on the surface of the ISS. Keywords: electrophysical measurements, sensors of the vibration type, flat probes, electric field, current leakage, geophysical structure, ionosphere


2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Lian he Li ◽  
Yue Zhao

Interaction of a screw dislocation with wedge-shaped cracks in one-dimensional hexagonal piezoelectric quasicrystals bimaterial is considered. The general solutions of the elastic and electric fields are derived by complex variable method. Then the analytical expressions for the phonon stresses, phason stresses, and electric displacements are given. The stresses and electric displacement intensity factors of the cracks are also calculated, as well as the force on dislocation. The effects of the coupling constants, the geometrical parameters of cracks, and the dislocation location on stresses intensity factors and image force are shown graphically. The distribution characteristics with regard to the phonon stresses, phason stresses, and electric displacements are discussed in detail. The solutions of several special cases are obtained as the results of the present conclusion.


2020 ◽  
pp. 108128652096564
Author(s):  
Yuanjie Huang

Dislocations and dislocation dynamics are the cores of material plasticity. In this work, the electric features of dislocations were investigated theoretically. An intrinsic electric field around a single dislocation was revealed. In addition to the well-known Peach–Koehler force, it was established that an important intrinsic electric force exists between dislocations, which is uncovered here for the first time and has been neglected since the discovery of dislocations. The electric forces may be large and sometimes could exceed the Peach–Koehler force for metals and some dielectric materials with large dielectric constant. Therefore, the electric force is anticipated to play a vital role in dislocation dynamics and material plasticity. Moreover, an external electric field could exert an electric force on dislocations and a threshold electric field was subsequently discovered above which this force enables dislocations to glide. Interestingly, it was found that some dislocations move in one direction, but others move in reverse in an identical electric field, which is in agreement with experimental observations. Despite dislocation motion under an electric field, to one’s surprise, both edge and screw dislocations do not carry net charges by themselves, which may tackle the long-standing puzzle on the charges of dislocations. These findings may supply people with new fundamental knowledge on dislocations as well as dislocation dynamics, and may assist people in understanding related phenomena.


2010 ◽  
Vol 02 (03) ◽  
pp. 585-615 ◽  
Author(s):  
BORIS D. PLYSHCHENKOV ◽  
ANATOLY A. NIKITIN

Numerical experiments based on Pride's model of electrokinetic phenomena have shown that electromagnetic Stoneley waves as well as pressure Stoneley waves are most sensitive to permeability variations. A new way for quantitative evaluation of any value of formation permeability is presented. It is based on simultaneous measurement of pressure field and axial component of electric field excited by an acoustic source in fluid-filled borehole with help from a set of receivers in borehole. Frequency dependence of ratio of the complex-valued amplitudes of the electric Stoneley wave to the pressure Stoneley wave obtained as a result of plane waves decomposition of pressure field and mentioned component of electric field carries important information about permeability. The ratio of the real part of this ratio to its imaginary part is very sensitive to permeability variations. The approximate analytical expressions for this ratio derived for open and sealed pores on borehole wall are base for construction of a new way of quantitative evaluation of formation permeability.


2018 ◽  
Author(s):  
V. S. Venediktov ◽  
P. K. Tretyakov ◽  
A. V. Tupikin

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