Low-frequency noise and inelastic tunneling spectroscopy in Fe(1 1 0)/MgO(1 1 1)/Fe(1 1 0) epitaxial magnetic tunnel junctions

Abstract We report on tunnelling magnetoresistance (TMR), current–voltage ( IV ) characteristics and low-frequency noise in epitaxially grown Fe(1 1 0)/MgO(1 1 1)/Fe(1 1 0) magnetic tunnel junctions (MTJs) with dimensions from 2×2 to 20×20 μm 2 . The evaluated MgO energy barrier (0.50±0.08 eV), the barrier width (13.1±0.5 A) as well as the resistance times area product (7±1 MΩ μm 2 ) show relatively small variation, confirming a high quality epitaxy and uniformity of all MTJs studied. At low temperatures ( T