Influence of Gas Type on the Laser Produced Graphite Plasma

Plasma graphite creation by a pulsed Nd: YAG laser with a wavelength of 1064nm to a target in vacuum in two cases (Argon, Air) with varied gas pressures and the resulting spectrum was diagnosed using optical emission spectroscopy for the wavelength range 320-740nm electron temperature Te and electron density ne Debye lengthλD , and plasma frequency f p were calculated. The results showed that increasing the pulse laser energy causes all plasma parameters of both gases under study to increase, as well as a rise in the emission line intensity. The ionization energy of target atoms determines the presence of an element’s atomic and ionic emission lines in the emission spectrum, increase in pressure decreases the electron temperature, and Debye length, also plasma frequency and electron density increase, as it has been proven that the type of gas does not affect the properties of plasma.

Laser-Induced Plasma Atomic and Ionic Emission During Target Ablation

This paper investigates the spectroscopy of plasma that resulted from the bombardment of ZnSe by using the optical emission spectroscopic (OES) technique. The plasma can be generated by the reaction between an Nd:YAG laser, with a wavelength of 1064[Formula: see text]nm with a repeat rate of 6[Formula: see text]Hz (as well as 9[Formula: see text]ns pulse duration), and a solid target, where the density of the electron (ne), the temperature of the electron ([Formula: see text]), the frequency of the plasma ([Formula: see text]) and the Debye length ([Formula: see text]) as plasma parameters, in addition to the particles’ number of Debye ([Formula: see text]) and plasma parameter ([Formula: see text]) have been calculated by picking up the spectrum of plasma at different energies (100, 200, 300, 400, 500) mj using Selenium (Se), Zinc (Zn) and the mixture (ZnSe) at ([Formula: see text]). It is found that the electron temperatures of Zn and Se ranged between (0.257–0.267)[Formula: see text]eV and (1.036–1.055) eV, respectively, while that of ZnSe ranged between (1.15–1.28)[Formula: see text]eV. This indicates that the electron temperature of ZnSe is higher than the temperatures of each Zn and Se.

Effect of Target properties on the Plasma Characteristics that produced by Laser at Atmospheric Pressure

In this paper, Al and Cu Plasmas that produced by pulsed Nd:YAG laser with fundamental wave length with a pulse duration of 6 nS focused onto Al and Cu targets in atmospheric air are investigated spectroscopically. The influence of pulse laser energy on the some Al and Cu plasmas characteristics was diagnosed by using optical emission spectroscopy for the wavelength range 320-740 nm. The results observed that the increase of pulse laser energy causes to increase all plasma characteristics of both plasmas under study and shown increasing of the emission line intensity. The appearance of the atomic and ionic emission lines of an element in the emission spectrum depends on the ionization energy of target atoms. The plasma characteristics are subjected to the ionization energy of the target element and laser energy.

Effect of Temperature and Magnetic Dopants on Particle size and Electrical Properties of ZnO Ceramic Varistor

We report here structural and electrical properties of Zn0.95 M0.05O ceramic, M = Zn, Co and Mn. It is found that addition of magnetic doping did not influence the hexagonal wurtzite structure of ZnO. Furthermore, the lattice parameters ratio c/a for hexagonal distortion and the length of the bond parallel u to the c axis were nearly unaffected. The average crystalline diameters, deduced from XRD analysis are 83.75, 72.86 and 70.97 nm for Zn, Mn and Co, which are 15 times lower than those obtained from FESEM micrographs (1570, 1380 and 1150 nm). The breakdown field EB was decreased as the temperature increased, in the following order: Mn> Zn > Co. The nonlinear region was observed for all samples as the temperature increased up to 400 K and completely disappeared with further increase of temperature up to 500 K. The values of nonlinear coefficient, α were between 1.65 and 56 for all samples, in the following order: Mn> Zn > Co. Moreover, the electrical conductivity σ was gradually increased as the temperature increased up to 500 K, in the following order: Co > Zn > Mn. On the other hand, the activation energies were 0.194, 0.155 eV and 0.231 eV for all samples, in the following order Mn, Zn and Co. These results have been discussed in terms of valence states, magnetic moment and thermo-ionic emission which were produced by the doping, and controlling the potential barrier of ZnO.