An ab initio study of novel quaternary Heusler alloys for spin polarized and waste heat recycling systems

In this paper, we employed density functional theory using WIEN2k to study structural, mechanical, electrical, magnetic and thermoelectric properties for quaternary Heusler alloys CoZrTiX(X = Ga, Si, Sn). The self -consistent field calculation is done with generalized gradient approximation procedure. The structural stability analysis shows that the CoZrTiX(X = Ga, Si, Sn) Heusler alloys are stable in Y-I type structure and having ferromagnetic property. In mechanical stability analysis we identified that all the reported Heusler alloys are ductile in nature. Electronic property calculations of CoZrTiX(X = Ga, Si, Sn) reveals that all are half-metal, having metallic nature in spin up channel and semiconducting nature in spin down channel. The calculated values of spin magnetic moments are consistent with Slater-Pauling rule. From the transport properties, we identified that both alloys CoZrTiGa and CoZrTiSn are showing better thermoelectric performance in higher temperature, while the alloy CoZrTiSi having reasonable ZT value at room temperature. Hence the reported Heusler alloys CoZrTiX(X = Ga, Si, Sn) can be potential candidates for spintronic and thermoelectric applications.