title: Hybridization Gap and Dresselhaus Spin Splitting in EuIr4In2Ge4.
abstract: EuIr4In2Ge4 is a new intermetallic semiconductor that adopts a non-centrosymmetric structure in the tetragonal I4̄2m space group with unit cell parameters a=6.9016(5) Å and c=8.7153(9) Å. The compound features an indirect optical band gap E(g)=0.26(2) eV, and electronic-structure calculations show that the energy gap originates primarily from hybridization of the Ir 5d orbitals, with small contributions from the Ge 4p and In 5p orbitals. The strong spin-orbit coupling arising from the Ir atoms, and the lack of inversion symmetry leads to significant spin splitting, which is described by the Dresselhaus term, at both the conduction- and valence-band edges. The magnetic Eu(2+) ions present in the structure, which do not play a role in gap formation, order antiferromagnetically at 2.5 K.
authors.affiliation: Department of Chemistry, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208 (USA).
authors.forename: Nicholas P
authors.initials: NP
authors.lastname: Calta
authors.affiliation: Department of Physics, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208 (USA).
authors.forename: Jino
authors.initials: J
authors.lastname: Im
authors.affiliation: Department of Chemistry, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208 (USA).
authors.forename: Alexandra P
authors.initials: AP
authors.lastname: Rodriguez
authors.affiliation: Department of Chemistry, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208 (USA).|Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (USA).
authors.forename: Lei
authors.initials: L
authors.lastname: Fang
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (USA).
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Bugaris
authors.affiliation: Department of Chemistry, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208 (USA).
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Chasapis
authors.affiliation: Department of Physics, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208 (USA).
authors.forename: Arthur J
authors.initials: AJ
authors.lastname: Freeman
authors.affiliation: Department of Chemistry, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208 (USA). m-kanatzidis@northwestern.edu.|Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (USA). m-kanatzidis@northwestern.edu.
authors.forename: Mercouri G
authors.initials: MG
authors.lastname: Kanatzidis
keywords: X-ray diffraction; crystal growth; electronic structure; hybridization; intermetallic phases