title: Dimensionality tuning of the electronic structure in Fe3Ga4 magnetic materials.
abstract: This work reports on the dimensionality effects on the magnetic behavior of Fe3Ga4 compounds by means of magnetic susceptibility, electrical resistivity, and specific heat measurements. Our results show that reducing the Fe3Ga4 dimensionality, via nanowire shape, intriguingly modifies its electronic structure. In particular, the bulk system exhibits two transitions, a ferromagnetic (FM) transition temperature at T1 = 50 K and an antiferromagnetic (AFM) one at T2 = 390 K. On the other hand, nanowires shift these transition temperatures, towards higher and lower temperature for T1 and T2, respectively. Moreover, the dimensionality reduction seems to also modify the microscopic nature of the T1 transition. Instead of a FM to AFM transition, as observed in the 3D system, a transition from FM to ferrimagnetic (FERRI) or to coexistence of FM and AFM phases is found for the nanowires. Our results allowed us to propose the magnetic field-temperature phase diagram for Fe3Ga4 in both bulk and nanostructured forms. The interesting microscopic tuning of the magnetic interactions induced by dimensionality in Fe3Ga4 opens a new route to optimize the use of such materials in nanostructured devices.
authors.affiliation: Instituto de Física "Gleb Wataghin", Universidade Estadual de Campinas (UNICAMP), Campinas-SP, 13083-859, Brazil.
authors.forename: K O
authors.initials: KO
authors.lastname: Moura
authors.affiliation: Núcleo Multidisciplinar de Pesquisa, Universidade Federal do Rio de Janeiro (UFRJ) - Campus Xerém, Duque de Caixias-RJ, 25245-390, Brazil.
authors.forename: L A S
authors.initials: LAS
authors.lastname: de Oliveira
authors.affiliation: Instituto de Física "Gleb Wataghin", Universidade Estadual de Campinas (UNICAMP), Campinas-SP, 13083-859, Brazil.
authors.forename: P F S
authors.initials: PFS
authors.lastname: Rosa
authors.affiliation: Instituto de Física "Gleb Wataghin", Universidade Estadual de Campinas (UNICAMP), Campinas-SP, 13083-859, Brazil.
authors.forename: C B R
authors.initials: CBR
authors.lastname: Jesus
authors.affiliation: Instituto de Física "Gleb Wataghin", Universidade Estadual de Campinas (UNICAMP), Campinas-SP, 13083-859, Brazil.|Brazilian Synchrotron Light Laboratory (LNLS)/Brazilian Center of Energy and Materials (CNPEM), Campinas-SP, 13083-970, Brazil.
authors.forename: M E
authors.initials: ME
authors.lastname: Saleta
authors.affiliation: Instituto de Física "Gleb Wataghin", Universidade Estadual de Campinas (UNICAMP), Campinas-SP, 13083-859, Brazil.
authors.forename: E
authors.initials: E
authors.lastname: Granado
authors.affiliation: Instituto de Física "Gleb Wataghin", Universidade Estadual de Campinas (UNICAMP), Campinas-SP, 13083-859, Brazil.
authors.forename: F
authors.initials: F
authors.lastname: Béron
authors.affiliation: Instituto de Física "Gleb Wataghin", Universidade Estadual de Campinas (UNICAMP), Campinas-SP, 13083-859, Brazil.
authors.forename: P G
authors.initials: PG
authors.lastname: Pagliuso
authors.affiliation: Instituto de Física "Gleb Wataghin", Universidade Estadual de Campinas (UNICAMP), Campinas-SP, 13083-859, Brazil.
authors.forename: K R
authors.initials: KR
authors.lastname: Pirota