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We theoretically conducted a study on the magnetic behaviors and magneto-caloric performance of the YTiO 3 compound, a studied system in this research paper. In accordance with the main objective if this paper, we restricted our research to only studying a number of the system-related elements such as the magnetization M(T), the inverse magnetization M−1 (T), the isothermal magnetic hysteresis loop (M − H), the magnetic entropy change (ΔS M), the relative cooling power (RCP) and the refrigerant capacity (RC). By so doing, we reached a number of results as: the inverse magnetization M−1 (T) , showed that the Curie temperature (T c) of the YTiO 3 compound was 26.5 K; the largest of the hysteresis loop H(M) at low temperatures indicates that the YTiO 3 compound belongs to hard magnetic materials; and at H = 5T, the maximum values of the magneto-caloric effect (MCE), which were represented by the magnetic entropy change (ΔS M), the relative cooling power (RCP), and the refrigerant capacity (RC), were found to be 1.91 J/kg K and 11.45 J/kg and 8.59 J/kg, respectively. • The YTiO 3 has been studied. • Thermal magnetization, Inverse magnetization of the system have been established. • Transition temperature has been deduced. • Isothermal magnetic entropy change, relative cooling power (RCP) and RC have been examined. [ABSTRACT FROM AUTHOR]

In this research, a simple theoretical method is proposed to investigate the electronic, magnetic and optical properties of Europium oxide (EuO) doped with 5% of (Ti, V, Cr and Fe). For a basic understanding of these properties, we employed Density-Functional Theory (DFT) based calculations with the Korringa-Kohn-Rostoker code (KKR) combined with the Coherent Potential Approximation (CPA). Also we investigated the half-metallic ferromagnetic behavior of EuO doped with 5% of (Ti, V, Cr and Fe) within the self-interaction-corrected Generalized Gradient Approximation (GGA-SIC). Our calculated results revealed that the Eu 0.95 TM 0.05 O is ferromagnetic with a high transition temperature. Moreover, the optical absorption spectra revealed that the half metallicity has been also predicted. [ABSTRACT FROM AUTHOR]

Using Monte Carlo simulations, we studied phase diagrams and magnetic properties of a ferromagnetic/antiferromagnetic Ising nanoparticles assembly with the spin-1/2 core and spin-3/2 shell. The system consists of nanocubes with equivalent exchange couplings of core and shell. However, the exchange couplings between the adjacent spins of the core and shell and between the nanocubes are assumed to vary. Thus, the effects of the exchange couplings and the system size on the phase diagrams are analyzing. Interesting behaviors are found when investigating the critical behavior of the system, the magnetizations, the magnetic susceptibility and the hysteresis loops. The increase of the core/shell size involves that of the temperature one. In addition, the increase in positive exchange interactions between the spins of the core and shell, on the one hand, and between the nanocubes, on the other hand, also increase the critical temperature, which favors the stable phase (3/2, 1/2). • Monte Carlo Simulation is used to study the magnetic properties of an assembly of cubic Core-Shell nanoparticles. • Phases diagrams of critical temperature with the exchange interactions and anisotropy parameter have been studied. • The increase of positive J2/J1 and J4/J1 increase the critical temperature, favoring the stable phase (3/2, 1/2). • Core and Shell sizes, anisotropy and interactions parameters effects on Magnetic hysteresis cycles are given. • Dependent coercivity with sizes and parameters of interactions are found. [ABSTRACT FROM AUTHOR]

Evaluating the properties of the magnetocaloric material regenerators is a crucial step in order to exploit them subsequently as the working substances in magnetic cooling devices. So, the main objective of this latter is to evaluate the electronic, magnetic properties as well as the magnetocaloric effect of HoN compound. To do so, a combination of DFT study and Monte Carlo simulations has been performed on HoN compound which undergoes a second-order ferromagnetic-paramagnetic phase transition. For this material, the temperature-dependent total magnetization, heat capacity and magnetic susceptibility have been calculated and are revealed that the curie temperature is acceptable concurrence with the experimental value. Furthermore, it was showed that under an applied magnetic field of 5T, the magnetocaloric effect (MCE) in regard to the maximum value of magnetic entropy change Δ S m a g m a x around its Curie temperature, agree well with the experimental one. Besides, the relative cooling power (RCP) values are found to be 28.5, 162.2 and 227 J. Kg−1 under different magnetic fields of 1,3 and 5T. All findings which are presented in the present work indicate that the large values of RCP and Δ S m a g m a x found in HoN are interesting for low-temperature magnetic refrigeration with excellent performance. • We have studied the magnetocaloric effect of the HoN compound. • We used the ab-initio calculations, the Monte Carlo simulation to study the magnetic properties. • A second-order ferromagnetic-paramagnetic phase transition about 15 K. • The magnetic moment and the exchange coupling interactions are calculated. [ABSTRACT FROM AUTHOR]

Evaluating the properties of the magnetocaloric material regenerators is a crucial step in order to exploit them subsequently as the working substances in magnetic cooling devices. So, the main objective of this latter is to evaluate the electronic, magnetic properties as well as the magnetocaloric effect of HoN compound. To do so, a combination of DFT study and Monte Carlo simulations has been performed on HoN compound which undergoes a second-order ferromagnetic-paramagnetic phase transition. For this material, the temperature-dependent total magnetization, heat capacity and magnetic susceptibility have been calculated and are revealed that the curie temperature is acceptable concurrence with the experimental value. Furthermore, it was showed that under an applied magnetic field of 5T, the magnetocaloric effect (MCE) in regard to the maximum value of magnetic entropy change Δ S m a g m a x around its Curie temperature, agree well with the experimental one. Besides, the relative cooling power (RCP) values are found to be 28.5, 162.2 and 227 J. Kg−1 under different magnetic fields of 1,3 and 5T. All findings which are presented in the present work indicate that the large values of RCP and Δ S m a g m a x found in HoN are interesting for low-temperature magnetic refrigeration with excellent performance. • We have studied the magnetocaloric effect of the HoN compound. • We used the ab-initio calculations, the Monte Carlo simulation to study the magnetic properties. • A second-order ferromagnetic-paramagnetic phase transition about 15 K. • The magnetic moment and the exchange coupling interactions are calculated. [ABSTRACT FROM AUTHOR]

Perovskite oxides have emerged as promising alternatives for photovoltaic devices due to their astonishing optoelectronic properties. Nevertheless, a density functional theory study was performed on the electronic, optical, and thermoelectric properties of ACoO 3 (A = Nd, Pr, and La) by TB-mBJ potentials. Based on the optimized structures, the observed results show that studied compounds display p-type semiconductor behavior with a bandgap of 1.95 eV, 1.08 eV, and 1.57 eV respectively. Hence, spherical charge density contours illustrate the ionic character of Nd/Pr/La/Co and O. The optical spectra are reported and discussed, the maximum absorption intensity for the LaCoO 3 is ∼20 × 104 cm around 400 nm. Furthermore, the figure of merit, the electrical and thermal conductivity of each compound are investigated by applying Boltzmann transport theory, the high mobility of carriers enhances the Seebeck coefficient and electrical conductivity of ACoO 3 (A = Nd, Pr, and La) materials. Our finding results make these materials favorable candidates for photovoltaic applications. • First-principles method was used to study the structural, electronic, optical and thermoelectric properties of oxide halide perovskite ACoO 3 (A = Nd, Pr or La). • The bandgap values of LaCoO 3 and NdCoO 3 are suitable for photovoltaic, optoelectronic devices. • The studied oxide halide perovskite ACoO 3 (A = Nd, Pr or La) show excellent light absorption in the visible range. • The NdCoO 3 exhibit high electrical conductivity. [ABSTRACT FROM AUTHOR]

The present study is carried out for investigating the half-metallic ferromagnetic behavior of C r and F e doped and co-doped G a N , respectively. To this end, ab-initio calculations using the Korringa-Kohn-Rostoker Green's function method coupled with the coherent potential approximation have been employed. In the background to make the study more useful, the first-principles computations were added and merged to the mean-field approximation and the Monte-Carlo simulation for the co-doped compound. Several variations were perceived in the results as in the bandgap energy, the energetic location of the transition-metal 3 d band and the X-ray absorption spectra. Besides, the stability of the system between the ferromagnetic and the spin-glass states is studied. Finally, we have integrated as input parameters in the classical Ising model by Monte-Carlo simulation, the exchange interactions obtained from ab-initio calculation, in order to confirm the half-metallic ferromagnetic states with high Néel temperature. • Study of half-metallic ferromagnetic behavior of Cr and Fe doped and co-doped GaN, respectively. • Ab-initio calculation and Monte Carlo Study (MCS) have been performed. • Half-metallic ferromagnetic states with high Neel temperature have been confirmed. [ABSTRACT FROM AUTHOR]

The structural, electronic, magnetic and magnetocaloric properties of metallic anti-perovskite Mn 3 InC compound are investigated using several theoretical methods such as: Ab-initio calculations and Monte Carlo simulations. Ternary manganese compounds Mn 3 InC have the cubic perovskite crystal structure, in which the Mn atoms are located at the face centered positions, the In atoms on the cubic corners and the C atoms at the body centered positions. Using the first principle calculations, the magnetic moment and the exchange coupling interactions values are calculated. The total magnetization and the susceptibility of this compound are determined. The critical temperature obtained is in good agreement with the experimental results. Obviously, the magnetic entropy change and relative cooling power (RCP) values for different external magnetic fields are obtained around T C. • The electronic structural, magnetic and magnetocaloric properties of metallic anti-perovskite compound Mn 3 InC are calculated. • These properties are determined using Ab-initio calculations and Monte Carlo simulations. • The total magnetization and the susceptibility of Mn 3 InC compound are determined. • The critical temperature obtained is in good agreement with the experimental results. • The magnetic entropy change and relative cooling power (RCP) for different external magnetic fields are obtained around T C. [ABSTRACT FROM AUTHOR]