Material designs of Fe-based superconductors and thermoelectric materials

Modern theoretical methods of structure prediction have been very successful in finding new interesting materials experimentally. They give a useful guideline to experiments for material synthesis and design. Notable recent successes are the prediction of superconductivity of hydrogen sulfide that has the highest critical temperature under high pressure [1, 2]. Other successes of theory-guided material searches are the prediction and synthesis of unreported missing half-Heusler compounds [3-5]. Using the ab initio evolutionary algorithm and electronic structure calculations we investigate the properties of two interesting materials: one is a new 112 family of Fe-based superconductor and the other is a new thermoelectric material, which is a material analog of the enigmatic thermoelectric FeSb₂. We also investigate the phase stabilities of both materials based on the accurate total energy calculations. Finally, we discuss the existence probabilities of both materials based on our recently proposed probabilistic model.

[1] Duan et al., Sci. Rep. 4, 6968 (2014).
[2] Drozdov et al., Nature 525, 73 (2015).
[3] Zhang et al., Adv. Funct. Mater. 22, 1425 (2012).
[4] Yan et al., Nat. Commun. 6, 7308 (2015).
[5] Gautier et al., Nat. Chem. 7, 308 (2015).