High quality Fe3-δO4/InAs hybrid structure for electrical spin injection

Single crystalline Fe3-delta O4 (0 <=delta <= 0.33) films have been epitaxially grown on InAs (001) substrates by molecular beam epitaxy using O-2 as source of active oxygen. Under optimum growth conditions, in situ real time reflection high-energy electron diffraction patterns, along with ex situ atomic force microscopy, indicate that (001) Fe3-delta O4 can be grown under step-flow-growth mode with a characteristic (root 2 X root 2)R45 surface reconstruction. X-ray photoelectron spectroscopy demonstrates the possibility of obtaining iron oxides with compositions ranging from Fe3O4 to gamma-Fe2O3. Measurements with a superconducting quantum interference device magnetometer at 300 K show good magnetic properties, suggesting that iron-based oxides may be promising for spintronic applications. (c) 2007 American Institute of Physics.