Optoelectronic and magnetic properties of Eu₂Si₅N₈. An ab-initio study

Eu₂Si₅N₈ is considered the most important compound in the development of inorganic materials with high potential and performance. Therefore, the electronic, magnetic and optical properties of Eu₂Si₅N₈ are investigated here using density functional theory. The electronic interactions are described within the generalised gradient approximation, GGA+U (where U is the Hubbard Coulomb energy term). The calculated energy gap was 3.5 eV for the investigated compound, resulting in a direct band gap semiconductor. The optical constants, including the dielectric function, refractive index, absorption coefficient, reflectivity, and energy loss function were calculated for radiation up to 14 eV. The optical properties demonstrate that the main differences in absorption, reflectivity, energy-loss function and refractive index occur in the infrared and visible regions for the spin-up and spin-down states, which makes this material an excellent candidate for optical memory devices.