Abstract
In this study, the electronic structure, chemical composition, and magnetic properties of multilayer ultrathin films of epitaxial maghemite (γ-Fe
2
O
3
/MgO)
N
were investigated. The multilayer structures of the (γ-Fe
2
O
3
/MgO)
N
ultrathin films were grown by molecular beam epitaxy (MBE) under ultrahigh vacuum on magnesium oxide substrates with different numbers of layers (where the number of layers,
N
= 2, 4, and 6). X-ray photoemission measurement (XPS) showed that the multilayer oxide films possessed only a single phase of maghemite γ-Fe
2
O
3
with full stoichiometry. The magnetic moment of all of the multilayer samples showed ferromagnetic behavior, with magnetizations close to the bulk value of γ-Fe
2
O
3
, which has not been previously observed or considered. Moreover, the magnetization increased as the number of layers increased. These findings show that the multilayer ultrathin γ-Fe
2
O
3
film possesses good magnetic properties that are close to those of the bulk of γ-Fe
2
O
3
, and will thus be useful in developing spintronic devices with good performance and other technological applications.