Related papers: Spin polarized tunneling in MgO-based tunnel junct…
A mesoscopic spin valve is used to determine the effective spin polarization of electrons tunneling from and into ferromagnetic transition metals at finite voltages. The tunneling spin polarization from the ferromagnet (FM) slowly decreases…
We report a two-step process for the fabrication of superconductor-insulator-normal metal tunnel junctions using NbN as the superconducting electrode and its surface oxide as the insulating tunnel barrier, and investigate its efficacy in…
In quasi-magnetic tunnel junctions (QMTJs) with a EuS spin filter tunnel barrier between Al and Co electrodes, we observed large magnetoresistance (MR). The bias dependence shows an abrupt increase of MR ratio in high bias voltage, which is…
Magnetoelectric properties of the spin-valve-type tunnel junction of Ta(5\ nm)/Ni$_{79}$Fe$_{21}$ (25 nm)/Ir$_{22}$Mn$_{78}$ (10 nm)/Co$_{75}$Fe$_{25}$ (4 nm)/Al (0.8 nm)-oxide/Co$_{75}$Fe$_{25}$ (4 nm)/Ni$_{79}$Fe$_{21}$ (20 nm)/Ta (5 nm)…
We demonstrate a spin diode consisting of a semiconductor free nano-scale Fe/MgO-based double tunnel junction. The device exhibits a near perfect spin-valve effect combined with a strong diode effect. The mechanism consistent with our data…
We present a detailed study of the spin-torque diode effect in CoFeB/MgO/CoFe/NiFe magnetic tunnel junctions. From the evolution of the resonance frequency with magnetic field at different angles, we clearly identify the free-layer mode and…
We provide compelling evidence to establish that, contrary to one's elementary guess, the tunneling spin polarization (TSP) of amorphous CoFeB is larger than that of highly textured fcc CoFeB. First principles atomic and electronic…
Planar macroscopic magnetic tunnel junctions exhibit well defined zero bias anomalies when a thin layer of ferromagnetic CoFe(B) nanodots is inserted within a MgO based tunnel barrier. The conductance curves exhibit a single and a double…
The electron tunneling in half metallic manganite tunnel junctions is studied by using a quantum mechanically treated double exchange model. We show that the stimulation of spin excitations, caused by the strong Hund's coupling between the…
The spin-torque in magnetic tunnel junctions possesses two components that both depend on the applied voltage. Here, we develop a new method for the accurate extraction of this bias-dependence from experiments over large voltage ranges. We…
Spin-polarized quasiparticles can be easily created during spin-filtering through a ferromagnetic insulator (FI) in contact with a superconductor due to pair breaking effects at the interface. A combination FI-N-FI sandwiched between two…
Electronic transport through a single-molecule magnet Mn$_{12}$ in a two-terminal set up is calculated using the non-equilibrium Green's function method in conjunction with density-functional theory. A single-molecule magnet Mn$_{12}$ is…
We report direct experimental evidence of room temperature spin filtering in magnetic tunnel junctions (MTJs) containing CoFe2O4 tunnel barriers via tunneling magnetoresistance (TMR) measurements.…
A method for measuring the degree of spin polarization of magnetic materials based on spin-dependent resonant tunneling is proposed. The device we consider is a ballistic double-barrier resonant structure consisting of a ferromagnetic layer…
Double layer two-dimensional electron systems at high perpendicular magnetic field are used to realize magnetic tunnel junctions in which the electrons at the Fermi level in the two layers have either parallel or anti-parallel spin…
We developed a parametrization of transmission probability that reliably captures essential elements of the tunneling process in magnetic tunnel junctions. The electronic structure of Fe/MgO system is calculated within the quasiparticle…
Magnetic tunnel junctions with crystalline MgO tunnel barrier and amorphous CoFeB electrodes received much attention due to their high tunnel magneto resistance ratio at room temperature. One important parameter for achieving high tunnel…
Experiments have shown that the tunneling current in a Co/Al$_2$O$_3$ magnetic tunneling junction (MTJ) is positively spin polarized, opposite to what is intuitively expected from standard tunneling theory which gives the spin polarization…
We observe spin-valve-like effects in nano-scaled thermally evaporated Co/AlOx/Au tunnel junctions. The tunneling magnetoresistance is anisotropic and depends on the relative orientation of the magnetization direction of the Co electrode…
We investigate the suitability of nearly half-metallic ferrimagnetic quaternary Heusler alloys, CoCrMnZ (Z=Al, Ga, Si, Ge) to assess the feasibility as electrode materials of MgO-based magnetic tunnel junctions (MTJ). Low magnetic moments…