Thermodynamic, electronic, magnetic, thermoelectric, and optical properties of full Heuslers compounds Co${}_2$TiAl(Ga, In). A First principles study

In this study, we investigated the thermodynamic, band structure, density of states, magnetic, thermoelectric and optical properties of Co${}_2$TiAl, Co${}_2$TiGa, and Co${}_2$TiIn full Heuslers in the L2${}_1$ phase via the full-potential linearized augmented plane wave (FP-LAPW) method. The results reveal that the system is more stable in the ferromagnetic state. The calculated elastic constants exhibit that these matters satisfy the criteria stability. The integer magnetic moment confirms the half-metallic behavior of Co${}_2$TiAl and Co${}_2$TiGa systems through GGA + U calculation. The optical properties of the bulk structures have confirmed its semiconducting behavior and its main optical response occurred in the infrared (IR) and visible ranges and the very low loss in the same region with existence absorption of these compounds, make them as suitable for optoelectronic applications. Further, the thermoelectric analysis has been carried out to survey the potential of these alloys for thermoelectric applications.