Coherent potential approximation

About: Coherent potential approximation is a research topic. Over the lifetime, 1930 publications have been published within this topic receiving 36805 citations.

Origin of Spin Reorientation Transitions in Antiferromagnetic MnPt-Based Alloys

Abstract: Antiferromagnetic MnPt exhibits a spin reorientation transition (SRT) as a function of temperature, and off-stoichiometric Mn-Pt alloys also display SRTs as a function of concentration. The magnetocrystalline anisotropy in these alloys is studied using first-principles calculations based on the coherent potential approximation and the disordered local moment method. The anisotropy is fairly small and sensitive to the variations in composition and temperature due to the cancellation of large contributions from different parts of the Brillouin zone. Concentration and temperature-driven SRTs are found in reasonable agreement with experimental data. Contributions from specific band-structure features are identified and used to explain the origin of the SRTs.

Effect of Tuning the Structure on the Optical and Magnetic Properties by Various Transition Metal Doping in ZnO/TM (TM = Fe, FeCo, Cr, and Mn) Thin Films

Abstract: We have investigated in this work the physical, optical, electronic, and the magnetic behavior (Curie temperature, magnetic moment) of Zn.1-x.MxO (M = Fe 5%, Co 1%, Cr 5%, and Mn 5%), diluted magnetic semiconductors (DMSs). The samples were deposited on glass substrate by the spray pyrolysis technique, and the results of the x-ray diffraction (XRD) of the prepared substrates was used to prove the incorporation of the dopants into the ZnO lattice host; the ferromagnetic and the antiferromagnetic state competitions and their effects on the physical, magnetic, and optical properties, were investigated. The electronic structure and magnetic properties of transition metal (TM) defects, were investigated in detail, by using the Korringa–Kohn–Rostoker (KKR) method combined with the coherent potential approximation (CPA). As a result, doping by TM impurities induce the ferromagnetism with different competitions between the ferromagnetic and antiferromagnetic states, which affects the physical properties of the TM (Fe, Fe/Co, Cr, and Mn)-doped ZnO, with a Curie temperature closer to room-temperature ferromagnetic.

Magnetic and electronic properties of the alloy system CuxRh1-x

Abstract: The electronic structure of the disordered substitutional alloy system CuxRh1-x has been studied by means of charge self-consistent Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA) calculations. The results of these investigations are used to discuss recent photoemission, susceptibility and NMR data on CuxRh1-x in detail.

Energy band of ternary alloy semiconductors—Calculation by a coherent‐potential approximation based on the method of linear combination of bond orbitals

Abstract: A method of calculating the effect of the random distribution of atoms on the energy‐band structure of ternary alloy semiconductors is proposed, where the coherent‐potential approximation based on the method of linear combination of bond orbitals (LCBO) is used. In the case of GaAscP1−c, the nonlinear dependence of the energy upon the alloy composition c at various symmetry points within the first Brillouin zone is calculated. It is found that the effect of disorder is an important factor in explaining the bowing effect of band gaps; In particular, the magnitudes of the direct gap Γv15→Γc1, and the indirect gap Γv15→Xc1 agree well with experimental results. The energy‐band structure, including the lifetime broadening of the energy at each Bloch state, is shown for GaAs0.5P0.5. Also, the relation between the LCBO parameters and the effect of disorder on various states is qualitatively discussed. The effect of disorder on the p‐like or s‐like states of the valence band increases with increasing the differen...