Electronic Band Structure of Various TiN/MgO Superlattices

Abstract

Various TiN(001)/MgO(001) superlattices have been investigated by using the total energy pseudopotential method. They are (TiN) n /(MgO) m as (TiN) 1 /(MgO) 7 , (TiN) 2 /(MgO) 6 , (TiN) 3 /(MgO) 5 , and (TiN) 2 /(MgO) 14. "n", "m", and "n + m" are TiN, MgO, and TiN/MgO layer numbers of superlattices in a supercell, respectively. Their relaxed superlattice structures and electronic properties were obtained. All the calculated electronic states of TiN/MgO superlattices correspond to metallicity. Values of an electrical conductance of the TiN/MgO superlattice along the c-axis around the Fermi level are quite small although its electronic structure is metallic. A Ti (N) atom at the TiN layer in (TiN) 1 /(MgO) 7 is replaced with Sc, V, and Nb (B, C, and O) as (ScN) 1 /(MgO) 7 , (VN) 1 /(MgO) 7 , and (NbN) 1 /(MgO) 7 ((TiB) 1 /(MgO) 7 , (TiC) 1 /(MgO) 7 , and (TiO) 1 /(MgO) 7). Their detailed electronic properties were investigated systematically.