Above room temperature Tc, 100% spin-polarization, and a high thermoelectric response in the ordered CaCu3Mn2Ir2O12

초록

Thermoelectric (TE), electronic, and magnetic properties of the CaCu3Mn2Ir2O12 structure were studied based on ab-initio approach. Ferromagnetic and two distinct ferrimagnetic (FiM)-I/FiM-II states were examined to figure out the stable magnetic ground state of the system. Our results revealed that antiferromagnetic interactions between Cu up arrow/Mn up arrow and Ir down arrow ions lead to a FiM-II. The charge transport potential for the system is assessed by estimating the various TE factors, where positive S represents the p-type semiconducting aspect and a high figure of merit of 0.95 at 300 K, validates the system potential for TE applications. Strikingly, the motif displays a 100% spin-polarization, holding an energy-gap of 0.7 eV in the spin-minority channel, which is high enough to restrict the spin-flipping. Further, the FiM-II ordering is verified from the calculated spin moment of 0.6/3.25/-0.57 mu B on the Cu/Mn/Ir ion and form spin-magnetization density isosurfaces. Finally, the estimated Curie temperature (Tc) is 322 K.

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