Investigation of possible half-metallic antiferromagnets on double perovskites La ABB'O_6 (4=Ca,Sr,Ba; B,B'= transition elements)

摘要

We thoroughly investigated all the possible (C_2~(29)=406 candidates of half-metallic (HM) antiferromagnet (AFM) with the structure LaSrBB'O_6, where BB' pairs are any combination of two 3d, Ad, and 5d transition elements. Sr was also replaced by Ca or Ba whenever HM-AFM was found and similar calculation was performed in order to probe more possibilities. We have found that LaAWXO_6, where A=Ca,Sr,Ba and X=Tc,Re are potential candidates of HM-AFM. Among those HM-AFM candidates, LaAWReO_6 (A=Sr,Ba) are rather robust than others for the structural optimization. Including previous Wang and Guo's work in 2006 and this work, we believe that we have found all possible HM-AFM candidates for double perovskites structure LaABB'O_6 (A = Ca,Sr,Ba and B,B' = transition elements).