Tuning the probability of defect formation: Substrate strains in SFMO
Sprache des Vortragstitels:
DPG Spring Meeting 2018
Sprache des Tagungstitel:
Since oxide materials like Sr2FeMoO6 are usually applied as thin films, we studied the effect of biaxial strain, resulting from a potential substrate, on the electronic and magnetic properties and, in particular, on the formation energy of point defects. From our first-principles calculations, we determined that the probability of forming point defects -- like vacancies or substitutions -- in Sr2FeMoO6 could be adjusted by choosing a proper substrate. For example, the amount of anti-site disorder and oxygen vacancies can be reduced with compressive strain to get purer Sr2FeMoO6 as needed for spintronic applications, while the formation of oxygen vacancies is more likely for tensile strain, which improves the functionality of Sr2FeMoO6 as basis material of solid oxide fuel cells. Hence, this degree of freedom might offer in general an additional possibility to tune the appearance of point defects besides e.g. experimental growth conditions like temperature or gas pressure.