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This work aims to assess the response of viscoelastic Kelvin–Voigt microscale beams under initial stress. The microbeam is photostimulated by the light emitted by an intense picosecond pulsed laser. The photothermal elasticity model with dual-phase lags, the plasma wave equation and Euler–Bernoulli beam theory are utilized to construct the system equations governing the thermoelastic vibrations of microbeams. Using the Laplace transform technique, the problem is solved analytically and expressions are provided for the distributions of photothermal fields. Taking aluminum as a numerical example, the effect of the pulsed laser duration coefficient, viscoelasticity constants and initial stress on photothermal vibrations has been studied. In addition, a comparison has been made between different models of photo-thermoelasticity to validate the results of the current model. Photo-microdynamic systems might be monolithically integrated on aluminum microbeams using microsurface processing technology as a result of this research.

Considering the Coulomb-hydrodynamic explosion induced by the interaction of a deuterium cluster target with ultra-intensity femtosecond laser, the mechanism which generates energetic deuterium nuclei for the fusion has been analyzed. The formulas for expansions of the deuterium ion cluster, which are driven by the Coulomb-hydrodynamic explosion, are proposed. Hence the kinetic energies of deuterium nuclei and the expansion time of deuterium ion cluster have been estimated.

Starting from a first-order approximate field description function for laser pulses, the method currently used to approximate chirped laser pulse (CLP) substitutes frequency and wave vector related variables with spatiotemporally varying functions. We investigated the error involved by calculating the relative deviation from Maxwell equations. Errors for the electric and magnetic fields are analyzed separately, and behaviors related to parameter changes (that is, in laser width, pulse duration and chirp parameter) were studied. Results show that aberration associated with currently used field-description functions for CLP increases monotonically with chirp parameter, and the deviation introduced by chirping is proportional to the relative frequency span of the laser. Simulations based on these functions will lead to considerable error, especially for laser pulses with large chirping.

This study focuses on electron acceleration and wakefield produced by Gaussian and Super-Gaussian (SG) laser pulses through plasma medium in the attendance of an external magnetic field. Two shapes of different laser spatial profiles Gaussian and SG are considered. Besides, governing equations for analysis of laser wakefield and electron acceleration by using of hydrodynamics fluid equations, Maxwell’s equations and perturbation technique for Gaussian and SG laser pulses in weakly nonlinear regime have been derived. In addition, influence of the external magnetic field strengths, laser intensity, the pulselength, the plasma electron density and the laser frequency on the wakefield and the electron energy gain have been investigated. Numerical results indicate that by increasing of external magnetic field, the amplitude of wakefield increases. Moreover, it is observed that wakefield amplitude excited by SG laser pulse in comparison with Gaussian laser pulse is larger when external magnetic field is increased. Furthermore, it is found that wakefield amplitude and shape of wakefield generation in within homogeneous plasma greatly are related to the laser profile type, selected laser parameters and external magnetic field. In addition, it is seen that influence of external magnetic field, while laser intensity enhances, on the electron energy gain in SG and Gaussian laser pulses is insignificant.

This paper deals with a two-temperature thermoelastic material subjected to a laser heating pulse as the heat source. Closed form solutions for the temperature and stress fields due to time exponentially decaying laser pulse are presented using the state-space approach. The Laplace transformation method is employed in deriving the governing equations. The inversion of Laplace transform is obtained numerically by using the Riemann-sum approximation method. The results have been presented in figures to show the effect of the time exponentially decaying laser pulse, the two-temperature parameter and the absorption coefficient on all the fields studied. The results show that the two-temperature parameter and the absorption coefficient parameter have significant effects on all the field parameters studied.

The paper presents the analytical solutions for a generalized thermoelastic medium consisting of microtemperatures and voids subjected to a laser pulse loading the medium thermally. The 0.02 ps pulse duration of the non-Gaussian laser beam is apt for heating a homogenous isotropic elastic half-space. A method called the normal mode analysis is employed to evaluate numerically the effects of various variables such as the micro-temperature vector, variation in the fraction field of the volume, first heat flux moment tensor, temperature distribution on the stresses and displacement components of the medium. In addition, the graphical illustration of the physical response of the medium has been presented in the presence and absence of void parameters, as well as in the presence of laser pulse with two different acting periods.

This study considers a thermoelastic micro-elongated solid which is being heated by a laser pulse in order to investigate the corresponding impact of thermal loading and magnetic field. A laser beam that is non-Gaussian in nature is used to heat the surface of the bounded plane with a pulse duration $0.0001$ps. The dual-phase-lag (DPL) model is considered to develop a better understanding of the problem. Also, the problems are solved using normal mode analysis as well as it helps in attaining the appropriate expressions for micro-rotation, components of displacement, the force stress, couple stress, concentration field, the temperature distribution the scalar micro-elongated function, and the micro-stress. The results obtained from the thermal variations are validated by comparing them to Coupled Theory (CT) of thermo-elasticity, Lord and Shulman (L–S) theory, and the DPL model. The graphical illustration of these comparisons has been presented as it helps in exploring the impacts of the laser pulse at two different times and the magnetic field parameter. The investigation also helped deduce some specific cases of interest.

This work aims to investigate the effects of magnetic field and inclined load on a two-dimensional thermoelastic medium under gravitational field. The problem is formulated in the context of refined dual-phase-lag Green–Naghdi (DPL GN) model. The bounding plane surface is heated by a non-Gaussian laser beam. The inclined load is supposed to be a linear combination of a normal load and a tangential load. Analytical formulas for several physical quantities are generated on the transformed domain using the Laplace and Fourier transform techniques. The inversion of double transform has been done numerically by using MATHEMTICA 10. The numerical inversion of Laplace transform is done by using the Zakian method (Halsted and Brown [Zakians technique for inverting Laplace transforms, J. Chem. Eng. 3 (1972) 312–313]). All physical quantities have been graphically depicted for the dual-phase-lag Green–Naghdi type III model (DPL GN-III), simple Green–Naghdi type III model (simple GN-III), Lord–Shulman model (LS) and classical thermoelasticity theory (CTE) to indicate the effect of magnetic field and the angle of inclination of the medium.

In this work, the influence of fractional-order derivative with two relaxation times in a thermoelastic medium under laser pulse is established. The surface of the half-space with free stresses is considered to be heated by a laser pulse. The exact analytical solution is adopted for the variations of temperature as well as the components of displacement and stress. Based on the eigenvalues approach and Laplace transform, the solutions of all variables have been obtained analytically. The results were graphically represented to show the effect of laser pulse in order to display the physical meaning of the phenomena. The graphical results indicate that the influence of fractional-order parameter plays an important role on all distributions.