Semiconductor Medium Research Articles

Effect of rotation and magnetic field on a numerical-refined heat conduction in a semiconductor medium during photo-excitation processes

A novel model in photo-thermoelasticity theory is investigated in the paper understudy. The model is obtained theoretically for a semiconductor elastic medium, which is in a rotation case. The interaction between main physical quantities during photothermal transport process is expressed in the governing equations. In addition, the numerical-refined multi-phase-lags relaxation times (thermal memories) are studied in the context of the heat equation when the medium is exposed to an external magnetic field. Moreover, the harmonic wave method in two-dimensional (2D) is introduced during the coupling processes between multi-waves. As such, the complete exact solutions of the main physical fields of semi-infinite semiconductor medium are obtained. Some plasma, mechanical and thermal forces are applied at the outer surface of the elastic medium to determine the unknown parameters. Many comparisons are displayed graphically when the physical constants of silicon (Si) material are used. Theoretical results are discussed under the impact of magnetic field and rotation field.

Thermal-microstretch elastic semiconductor medium with rotation field during photothermal transport processes

A mathematical novel model for elastic semiconductor medium with microstretch properties is investigated. The generalized model is studied in the context of photo-thermoelasticity theory when the semiconductor medium is excited. The governing equations describe the coupled between the propagation of the elastic-thermal-plasma waves when the thermo-microstretch elastic semiconductor material is studied during a rotation field. The linear medium has an isotropic properties. The photothermal transport processes occurs during a two-dimension elastic and electronic deformation when the microinertia of microelement is taken into account. The harmonic wave method can be used to obtain the general solutions for the basic physical variables. The complete analytical solutions of the considered variables are obtained when some mechanical-thermal and plasma conditions are applied on the boundary of the semiconductor medium. The numerical simulations of silicon and germanium media are constructed graphically with many comparisons according to a new parameters with thermal memories and rotation parameter.

Trapping of Electrons around Nanoscale Metallic Wires Embedded in a Semiconductor Medium

We predict that conduction electrons in a semiconductor film containing a centered square array of metal nanowires normal to its plane are bound in quantum states around the central wires, if a positive bias voltage is applied between the wires at the square vertices and the latter. We obtain and discuss the eigenenergies and eigenfunctions of two models with different dimensions. The results show that the eigenstates can be grouped into different shells. The energy differences between the shells is typically a few tens of meV, which corresponds to frequencies of emitted or absorbed photons in a range of 3THz to 20THz approximately. These energy differences strongly depend on the bias voltage. We calculate the linear response of individual electrons on the ground level of our models to large-wavelength electromagnetic waves whose electric field is in the plane of the semiconductor film. The computed oscillator strengths are dominated by the transitions to the states in each shell whose wave function has a single radial node line normal to the wave electric field. We include the effect of the image charge induced on the central metal wires and show that it modifies the oscillator strengths so that their sum deviates from the value given by the Thomas-Reiche-Kuhn rule. We report the linear response, or polarizability, versus photon energy, of the studied models and their absorption spectra. The latter show well-defined peaks as expected from the study of the oscillator strengths. We show that the position of these absorption peaks is strongly dependent on the bias voltage so that the frequency of photon absorption or emission in the systems described here is easily tunable. This makes them good candidates for the development of novel infrared devices.

Thermal conductivity changes of photo-elastic semiconductor excited in gravitational field with hydrostatic initial stress and internal heat source

In this work, the effect of hydrostatic initial stress is studied with the exited semiconductor material. Electrons are exited at the free surface of the elastic semiconductor medium using the photo-thermal-elastic theory during the transport (diffusion) process. The thermal memories are due to the dual-phase-lag (DPL) relaxation times of the heat conduction equation with a novel model. In this model, the thermal conductivity is chosen as a linear dependent function of the thermal temperature impact which is variable. The effect of gravitational field is taken into account during the two-dimensional (2D) elastic deformation under the impact of an internal heat source. The Kirchhoff transformation mapping is used. The harmonic wave (normal mode) method is applied for the 2D governing equations to obtain the main physical fields analytically. Some thermal and mechanical forces are applied with other elastic-plasma conditions at the free surface of the semiconductor material to get the complete solutions. Some comparisons used a novel parameters which depend on the DPL model and the differences in the thermal conductivity parameters and they are illustrated graphically and discussed.

Metal–insulator–metal waveguides with lateral electrical pumping

Metal–insulator–metal (MIM) waveguides are demonstrated which have electrically pumped semiconductor gain medium at their core. In particular electrical contacts are made well away from the optical mode and carriers are transported to the gain medium via semiconductor pathways a few tens of nanometers thick. Wet chemical etching is employed to form the gain medium cores, which can have widths on the order of 150 nanometers (nm). Total thickness of the layers between the metal sheets in the MIM structure is approximately 260 nm. Spectra obtained from devices with wider core widths operating at low temperatures and wavelengths near 1550 nm are examined. The nanowire like gain medium cores have an approximately rectangular cross section. Key process steps to form these waveguide structures with their electrically pumped cores are also described.

Photo-elastic-dynamic impacts of the Hall current with rotation in ramp-type heating microelement semiconductor medium

In this discussion, the focus is on studying the coupling between the strong external magnetic field, which falls on the excited semiconductor material. The microelements with microtemperature process inside the medium are taken into consideration. The photo-thermo-elasticity theory is used in the presence of rotation field and Hall current. The two-dimensional deformation for governing equations is taken to discuss the main model of the photo-thermo-elasticity theory in dimensionless formation. The elastic-plasma-thermal transport in the context of the magnetic field has been constructed. The mathematical technique by the Fourier and Laplace transformations is used to remove one space–time variable in the physical domain. The impact of microtemperature vector inside the medium is considered. To obtain the main physical quantities in the time domain, the ramp-type heating is used at the free surface with other mechanical-elastic-plasma conditions when the inversion of Fourier and Laplace integrals was used with some numerical technique. Many comparisons under the effect of Hall current are made. Some physical quantities are graphed and discussed.

Parametric oscillation of acoustical phonon mode in magnetized doped III–V semiconductors

Using the hydrodynamic model of semiconductor plasmas and coupled mode theory of interacting waves, we develop a theoretical formulation followed by numerical analysis to study parametric oscillation of acoustical phonon mode in magnetized doped III–V semiconductors. The origin of nonlinear interaction is assumed to lie in effective second-order optical susceptibility ( $$\chi^{(2)}$$ ) arising due to nonlinear induced current density and acousto-optic polarization of the semiconductor medium. Expressions are obtained for threshold pump intensity ( $$I_{{0,{\text{th}}}}$$ ) and operational characteristics such as conversion efficiency ( $$\eta_{k}$$ ) and single pass signal power gain ( $$g_{{{\text{sp}}}}$$ ) of the proposed single resonant optical parametric oscillator. Numerical analysis is made for a representative n-InSb crystal irradiated by 10.6 µm pulsed CO2 laser. The effects of some important parameters including external magnetic field ( $$B_{0}$$ ), mirror reflectivity ( $$R$$ ), crystal length ( $$L$$ ), etc. on $$I_{{0,{\text{th}}}}$$ , $$\eta_{k}$$ and $$g_{{{\text{sp}}}}$$ of the single resonant optical parametric oscillator are analyzed in detail. The analysis establishes the technological potentiality of magnetized doped III–V semiconductors as the hosts for fabrication of highly efficient and widely tunable single-resonant optical parametric oscillators.

Influence of variable thermal conductivity on wave propagation for a ramp-type heating semiconductor magneto-rotator hydrostatic stresses medium during photo-excited microtemperature processes

The interaction between the exited semiconductor medium with the induced magnetic field is investigated. The medium is taken during a microtemperature process in hydrostatic initial stresses. The problem is studied when the thermal conductivity is variable that depends on the temperature (which can be taken in a linear form of temperature). The main quantities are obtained in the context of the photo-thermoelasticity theory when the medium is in a rotator case. The two dimensions (2D) deformation equations are obtained during the thermo-elastic-plasma transport processes. The governing equations can be investigated under the integral transformations of Fourier and Laplace with the impact of microelements vector. The basic analytical solutions of the physical quantities in this phenomenon are obtained under transformations in the physical domain. The thermal ramp type (heating type) is used with some othermechanical-plasma conditions which they can be applied at the free external surface. To obtain the main solutions of basic quantities in space–time domain, some inversion methods of Fourier and Laplace transformations are applied numerically. Many comparisons between several parameters are made numerically and they are shown graphically and discussed.

Photo-thermo-elastic interaction in a semiconductor material upon hyperbolic two-temperature and thermal relaxation times

ABSTRACT In the present work, the hyperbolic two-temperature model with one thermal relaxation time is utilized to study the photo-thermal interactions in semiconductor media. The variations of the carrier density, the thermodynamic, the conductive temperatures, the stress and the displacement in a semi-infinite semiconductor material have been estimated. The material is considered to be an isotropic, homogeneous semiconductor medium. By using Laplace transforms with the eigenvalues methodology, the exact solutions of all physical quantities are obtained. Finally, the numerical results are presented graphically to show the difference between the generalized classical two-temperature model, the generalized hyperbolic two-temperature model, the generalized thermo-elastic model and the one temperature model.

Temperature dependent thermal conductivity during photothermal excitation process of semiconductor medium with an internal heat source in gravitational field

In this work, a novel model of semiconducting elastic material is studied during a process of photothermal excitation. The dual phase lag (DPL) for the heat conduction equation is introduced in the context of the variable of the thermal conductivity. The thermal conductivity can be chosen as a linear function of temperature (depend on temperature). The generalized thermoelasticy theory is investigated when an internal heat source is steady with a constant speed in the context of the gravitational field. The harmonic wave technique is used in two-dimensional deformations to obtain the considered physical fields. Some thermal loading subjected to thermal shock and other mechanical forces at the outer free surface of a semi-infinite elastic medium (semiconductor as silicon) are applied. The considered physical fields were illustrated graphically. The influences of some several variables are obtained which based on the DPL (thermal memories) model and the variable thermal conductivity. The results obtained are investigated and are depicted graphically.

A rotational gravitational stressed and voids effect on an electromagnetic photothermal semiconductor medium under three models of thermoelasticity

In the current article, the main aim is to investigate a new model on a volume fraction, photothermal, initial stress, electromagnetic field, gravity, and rotation effect on an isotropic homogeneous semiconducting generalized thermoelasticity solid under three thermoelastic models viz: classical dynamical (CD), Lord–Shulman (LS), and dual-phase-lags (DPL). The basic governing equations of the problem are presented considering voids, electromagnetic field, photothermal, initial stress, gravitational, rotation, and semiconducting in the context of the model of generalized thermoelasticity. The normal mode analysis method has been applied for solving the partial differential equations to this phenomenon under the assumption boundary conditions. The obtained results see that the photothermal, rotation, electromagnetic field, voids, the process of semiconductor, initial stress, gravity, and thermal relaxation time took a significant role on the phenomenon. The physical quantities with some comparisons are introduced analytically and presented by figures to clear the impact of the external parameters and agreement with the previous and practical results.

A photo-thermal interaction in semi-conductor medium with cylindrical cavity by analytical and numerical methods

In this work, we compare the analytical solutions with the numerical solutions for photothermal interactions in semiconductor medium containing cylindrical cavity. This paper is devoted to a study of the photothermal interactions in semiconductor medium in the context of the coupled photo-thermal model. The basic equations are formulated in the domain of Laplace transform and the eigenvalue scheme are used to get the analytical solutions. The numerical solution is obtained by using the implicit finite difference method (IFDM). A comparison between the analytical solution and the numerical solutions are obtained. It is found that the implicit finite difference method (IFDM) is applicable, simple and efficient for such problems.

The Hyperbolic Two Temperature Semiconducting Thermoelastic Waves by Laser Pulses

A novel model of a hyperbolic two-temperature theory is investigated to study the propagation the thermoelastic waves on semiconductor materials. The governing equations are studied during the photo-excitation processes in the context of the photothermal theory. The outer surface of o semiconductor medium is illuminated by a laser pulse. The generalized photo-thermoelasticity theory in two dimensions (2D) deformation is used in many models (Lord–Shulman (LS), Green–Lindsay (GL) and the classical dynamical coupled theory (CD)). The combinations processes between the hyperbolic two-temperature theory and photo-thermoelasticity theory under the effect of laser pulses are obtained analytically. The harmonic wave technique is used to obtain the exact solutions of the main physical fields under investigation. The mechanical, thermal and recombination plasma loads are applied at the free surface of the medium to obtain the complete solutions of the basic physical fields. Some comparisons are made between the three thermoelastcity theories under the electrical effect of thermoelectric coupling parameter. The influence of hyperbolic two-temperature, two-temperature and one temperature parameters on the distributions of wave propagation of physical fields for semiconductor silicon (Si) medium is shown graphically and discussed.

Generalized photo-thermo-microstretch elastic solid semiconductor medium due to the excitation process

A novel model in the photo-thermoelasticity theory with microstretch properties is studied. The plasma-elastic-thermal plane waves are propagated in a linear isotropic generalized photo-thermo-microstretch elastic semiconductor solid medium. The photothermal excitation occurs in the context of the microinertia of the microelement process during two-dimensional (2D) deformation. The harmonic wave techniques are used to get the solutions for the basic variables. The analytical solution of the main physical fields; carrier intensity, normal displacement components, temperature, stress load force, microstress and tangential coupled stress can be obtained. Some graphics illustrated when using the plasma, thermal and mechanical load boundary conditions are applied at the outer free surface of the elastic medium. Some semiconductor materials, as silicon (Si) and Germanium (Ge), are used to make the numerical simulation and some comparisons in different thermal memories are made. The main physical variables with new parameters are discussed theoretically and shown graphically.

A study on photo-thermo-elastic wave in a semi-conductor material caused by ramp-type heating

A mathematical model of the Green-Naghdi photo-thermoelastic model due to ramp-type heating is presented to study the photo- thermo-elastic waves in a two-dimension semi-conductor material. By using Fourier and Laplace transforms with the eigenvalue scheme, the variables are analytically obtained. A semiconductor media such as silicon is investigated. Numerical outcomes for all the physical quantities are implemented and illustrated graphically. The results show that the ramp-type source has varying degrees of influence on physical quantities. The derived methods are evaluated with numerical outcomes which are applied to the semi-conductor material in simplified geometry. Finally, it can be found that the ramp-type heating source has great effects on the studying fields.

Refined heat conduction equation of thermomagnetic microtemperature semiconductor material during photothermal excitation process

ABSTRACT In this problem, the coupled between magnetic field and thermal-elastic-plasma waves is studied. The governing equations are taken during photothermal excitation on a surface of semiconductor medium. The medium is exposed to weak external magnetic field during the refined multi-phase-lags of thermal relaxation times. The microelements (microtemperatures) possess due to microstructure of the semiconductor medium is investigated. The normal mode method is applied in one dimension (semiconductor rod) to obtain the main physical fields in this phenomenon for this microtemperature field. The surface is shocked by heating (thermal shock problem) and applying the free traction on its outer surface (mechanical boundary) through transport (diffusion) process of temperature to observe the analytical complete expressions of the main physical fields. The silicon (Si) material is used to make a simulation and obtain the numerical results. The basic physical field quantities are graphed and discussed.

Plasma-elastic-thermal propagation of a rotator semiconductor magneto-electric medium during microtemperature and photothermal excitation processes subjected to mechanical ramp type

ABSTRACT The overlapping between the initial magnetic field and the generalized thermoelasticity theory during the excited semiconductor medium is studied. The microtemperature process in the context of the photothermal theory (due to the thermal effect) is obtained for the main fields of a rotator medium. The disturbances of the elastic-plasma-thermal waves are investigated in two-dimensional (2D) deformation. The governing equations are discussed in the Fourier and Laplace domains when microelements possess microtemperatures. The basic analytical solutions of the main variables are constructed with Laplace transform. The boundary conditions as well as mechanical ramp and isothermal type are applied on the outer surface of the semiconductor elastic medium to obtain the unknown parameters. The complete solutions of the main variables field in the space-time domain are observed when the inversion techniques are used numerically. The effects of parameters of rotation, thermoelectric coupling, and magnetic field are discussed theoretically and graphically in 2D and 3D.

Photothermal Excitation Process during Hyperbolic Two-Temperature Theory for Magneto-Thermo-Elastic Semiconducting Medium

A novel technique is used to study the magnetic field influence in the free surface of an elastic semiconductor medium for a one-dimensional (1D) deformation. The problem is formulated during the hyperbolic two-temperature theory to study the coupled between the plasma, thermo-elastic waves. The investigation is conducted during a photothermal transport processes with the effects of both initial hydrostatic stress and some mechanical force. Using the Laplace transform method, the governing equations of the elastic waves, carrier density, quasi-static electric field, heat conduction equation, hyperbolic two temperature coefficient and constitutive relationships are obtained for the thermo-magnetic-electric medium. The mechanical stresses, thermal and plasma boundary conditions are applied on the interface adjacent to the vacuum to obtain the basic physical quantities in Laplace domain. The inversion of Laplace transform with numerical method is applied to obtain the complete solutions in time domain for the main physical fields under investigation. The effects of thermoelectric, thermoelastic and hyperbolic two temperature parameters of the applied force on the displacement component, carrier density, force stress and temperature distribution have been discussed graphically.

Thomson effect in thermo-electro-magneto semiconductor medium during photothermal excitation process

ABSTRACT The effect of Thomson heating on semiconductor medium is studied. Analytical discussions in the presence of thermoelectricity and magnetic field, in the context of photothermal transport process, are made. The interactions between plasma, thermoelectric, magnetic and elastic waves are taken into consideration. The governing equations are investigated in two-dimensional deformations of a homogenous, isotropic medium. The density of charge is taken only as a function of time of the induced electric current. The normal mode technique is used to obtain the physical quantities field under investigation. Some electro-mechanical loads and thermal effect through recombination process are applied at the free surface of semiconductor elastic medium. The distributions of physical fields in this phenomenon are discussed and represented graphically. The results have been discussed under the effects of thermoelectric parameter and Thomson parameter.

Response of Mechanical Ramp Type of Semiconductor Magneto-Rotator Medium with Variable Thermal Conductivity during Photo-Excitation Microelement Processes

The effect of external magnetic field during microelement processes is used to discuss the excited semiconductor medium in generalized thermoelasticity theory. The thermal conductivity which depends on the temperature is investigated in the context of the photothermal theory to obtain the main variables for a rotator elastic semiconductor medium. In this case the thermal conductivity is variable. The elastic-plasma-thermal waves in two-dimension (2D) deformation have been constructed. Fourier and Laplace integral transformations are used to solve the main governing equations under the effect of microtemperature vector field. Analytical solutions of the main physical field quantities are obtained under these transformations to get the solutions in the physical domain. The mechanical ramp type condition and some other thermal-elastic-plasma conditions are applied on the outer free surface of the medium. To obtain complete solutions for the basic physical quantities, numerical inversion methods of Fourier and Laplace transformations are used in space-time physical domain. Some comparisons are made for some several parameters that they represent graphically and discussed.