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- ItemSTRUCTURAL, ELECTRONIC, MAGNETIC, AND ELASTIC PROPERTIES OF THE FULL-HEUSLER COMPOUNDS: CO2MNSI, CO2MNGE USING FP-LAPW METHOD(An-Najah National University, 2025-02-13) Hasan, DuaaThe Structural, electronic, magnetic, and elastic properties for both normal and inverse full-Heusler compounds Co2MnSi and Co2MnGe were investigated by using full potential linearized augmented plane wave (FP-LAPW) method, within density functional theory (DFT) that implemented in WEIN2k package. The generalized gradient approximation (GGA) has been used to compute the structural properties such as lattice parameter (a), bulk modulus (B), it’s first pressure derivative (B') and minimum energy (E0). Moreover, electronic,magnetic and elastic properties were found using GGA. In addition to GGA, modified Becke-Johnson Potential (mBJ) was used to enhance the band structure (BS). According to the density of states (DOS) and BS, both normal Co2MnSi and Co2MnGe compounds have half-metallic behavior, while invers Co2MnSi and Co2MnGe compounds are metallic. both normal and inverse Co2MnSi and Co2MnGe compounds are ferromagnetic materials. The normal Co2MnSi and Co2MnGe compounds and inverse Co2MnSi are mechanically stable, whereas inverse Co2MnGe compound is mechanically unstable. According to anisotropic factor (A), normal and inverse Heusler compounds Co2MnSi and normal Heusler compound Co2MnGe are elastic anisotropy. Pugh ratio (B/S) indicates that both normal and inverse Heusler compounds Co2MnSi, and normal Heusler compound Co2MnGe are ductile. According to Poisson’s ratio (ν) normal and inverse Heusler compounds Co2MnSi and normal Heusler compound Co2MnGe have ionic bonds.
- ItemINVESTIGATION OF ELECTRICAL, OPTICAL AND MORPHOLOGICAL PROPERTIES OF SILVER NANOPARTICLES (Ag NPs) SYNTHESIZED BY MICROWAVE-ASSISTED (MW) SYNTHESIS METHOD(An-Najah National University, 2025-01-29) Habbash, ShahdNanoparticles (NPs) are very small-sized particles with a diameter ranging between 1 to 100 nm. Metallic nanoparticles take a huge place in recent researches because of its importance in different fields; electrical, optical, industrial and more. Among the known metals, silver (Ag) is the most especial one due to its physical and chemical properties. Several methods were used to prepare silver nanoparticles. The microwave-assisted synthesis method (MW) is the easiest way in which the Ag NPs can be synthesized in a very short time (some seconds), with high yield and controlled synthesis conditions. In this study, the Ag NPs were successfully prepared using the MW method. In the preparation process we used the precursor Silver Nitrate (AgNO3), with Ethylene Glycol as a reducing agent and polyvinylpyrrolid (PVP) as a stabilizing agent. The synthesis conditions were controlled during the preparation method. These conditions are the power of the microwave (Medium-Low, ML, Medium, M, Medium-High, MH, and High, H), the microwave heating time (30s and 90s) and the ratio between the precursor to stabilizing agent, AgNO3: PVP (1:1/2,1:1,1:2,1:3). The prepared samples were characterized using the ultra-violet visible absorption spectroscope (UV-vis). It is clear that both times can be used successfully to prepare Ag NPs, this is obtained from the peak of surface-plasmon resonance band (SPR) which exist in the correct region (400-450) nm. The atomic force microscope (AFM) was used to study the morphological properties of the prepared samples (size and shape). All samples have a spherical shape of the Ag NPs with different sizes. An enhancement of the Ag NPs size occurs by either increasing the MW power, increasing the MW heating time, or decreasing the PVP ratio. The electrical properties of the same samples were studied using the vector network analyzer (VNA). The 30s samples are not stable, while the 90s samples give stable measurements, and repeating measurement process after a long time (up to 7 months) gives approximately the same results for these 90s samples.
- ItemSTRUCTURAL, ELECTRONIC, MAGNETIC, AND ELASTIC PROPERTIES OF THE FULL-HEUSLER COMPOUNDS: Sc2ZrAl, Sc2ZrIn USING FP-LAPW METHOD.(An-Najah National University, 2024-07-03) Gharabah, RubaStructural, electronic, elastic, and magnetic properties of the Full-Heusler Compounds: Sc2ZrAl, Sc2ZrIn have been investigated and examined by utilizing full potential linearized augmented plane wave method (FP-LAPW). This method provides more accurate estimations of the electronic structure of atoms. We have used the Density Functional Theory (DFT), which is a computational quantum mechanical modelling method being implemented in the WIEN2k package. FP-LAPW method is an application of Kohn-Sham (DFT), which typically goes with the study of core and valence electrons, the ground state density, total energy, and Kohn-Sham eigenvalues (energy bands) of a many-electron system. Structural parameters (bulk modulus, lattice parameters and first pressure derivatives) have been investigated by applying the generalized gradient approximation (PBE-GGA). Also, the modified Becke-Johnson (mBJ) was used computationally to develop and enhance the calculated value of energy band gap for these compounds. Mechanically, we identified that the normal full-Heusler compounds Sc2ZrAl and Sc2ZrIn were stable, while the inverse full-Heusler compounds Sc2ZrAl and Sc2ZrIn were unstable. This result agrees with previous studies.
- ItemWAFER PROBING MEASUREMENTS OF ITkPix-V1 FOR ITk PIXEL ATLAS UPGRADE(An-Najah National University, 2024-07-22) Salahat, HosniaThis thesis is related to a Toroidal LHC Apparatus (ATLAS), the biggest general-purpose detector at the Large Hadron collider (LHC). Inside the LHC ring, two high energy hadron beams collide. This collision needs to be detected to check the predictions of particle physics theories, such as the properties of the Higgs boson, which is so crucial to the Standard Model. For that, ATLAS and other detectors were built. Researchers need to boost the LHC's performance by increasing its integrated luminosity by a factor of ten beyond its design value to maximize discoveries possibility in 2029, known as the High Luminosity-Large Hadron Collider (HL-LHC) plan. ATLAS detector is going under upgrading processes to cope with this higher luminosity, in which its inner detector (ID) that is composed partially of silicon is going to be replaced by a new inner tracker (ITk) consists completely of silicon. The new ITk is composed of a strip detector and pixel detector. The building blocks of the ITk’s pixel detector are the pixel modules which contains readout chips called the ITkPix-V1. Those chips are going under tests to check its suitability to be used in the new ITk. One of those tests is the wafer probing tests. In Laboratoire De Physique Des 2 Infinite Irène Joliot-Curie (IJCLab), the wafer propping set-up used for this task has to undergo a quality control process to decide its fit to do the tests on the chips, so the main topic of this thesis is analyzing the results of the tests done by the wafer probing set-up of IJCLab on the ITkPix-V1 chips and comparing it to reference measurements done by the University of Bonn on the same chips in order to help qualifying the set-up of IJCLab to do the wafer probing tests. Part of the test results were similar to the reference results while some were not. Depending on the analysis done, some reasons that cause the non consistent results were found. Key Words: ATLAS, LHC, HL-LHC, ITk, ITkPix-V1.
- ItemELECTRIC FIELD EFFECT IN MONOLAYER OF GRAPHENE(2022-09-05) Salsabeel Khalel SalehBackground: Graphene is a two-dimensional nanomaterial. The theory of graphene was laid out for the first time in 1947when P. R. Wallace looked at the electronic band structure of graphene. Many researchers have studied the properties of graphene in the presence of an electric field. This study has looked at the dynamics of electron in a two- dimensional monolayer graphene in the presence of a static and uniform electric field. Three different orientations of the electric field have been considered: E ⃗=E_x i ̂ ,E ⃗=E_y j ̂ and E ⃗=E_x i ̂+E_y j ̂ where x and y are arbitrary directions. Methodology: The dynamical expressions for the velocity and position of an electron in an oriented- electric field have been derived from the dispersion relation. The figures in the calculations were drawn by using the Mathematica program. Results: The electric field depended on the frequency of w_B.Because the electric field E ⃗ is implicitly related to electron momentum k_xand k_y, it was possible control it as they change. Moreover, when the applied electric field E ⃗ is in the x and y direction together the electron's behavior in the monolayer graphene is influenced by an angle α. Conclusion: These findings showed that if an electric field E ⃗ is applied to an electron along the x axis, the electron's Bloch oscillation would disappear in the x direction but would never happen in the y direction. And the electron's movement over the Dirac points would double the amplitude and period. Keywords: Electric field; Bloch oscillation; graphene; position; velocity.