Resonant Inversion of Tunneling Magnetoresistance

Resonant inversion of tunneling magnetoresistance.

Resonant tunneling via localized states in the barrier can invert magnetoresistance in magnetic tunnel junctions. Experiments performed on electrodeposited Ni/NiO/Co nanojunctions of area smaller than 0.01 microm(2) show that both positive and negative values of magnetoresistance are possible. Calculations based on Landauer-Büttiker theory explain this behavior in terms of disorder-driven stati...

Theory of digital magnetoresistance in ferromagnetic resonant-tunneling diodes

We propose a ferromagnetic spintronic system, which consists of two serial connected resonant-tunneling diodes. One diode is nonmagnetic whereas the other comprises a ferromagnetic emitter and quantum well. Using a self-consistent coherent transport model we show that the current-voltage characteristic of the ferromagnetic diode can be strongly modulated by changing the relative orientation of ...

Effects of resonant interface states on tunneling magnetoresistance

Based on model and ab initio calculations we discuss the effect of resonant interface states on the conductance of epitaxial tunnel junctions. In particular we show that the ‘‘hot spots’’ found by several groups in ab initio calculations of symmetrical barriers of the ki-resolved conductance can be explained by the formation of bonding and antibonding hybrids between the interface states on bot...

Observation of resonant tunneling in silicon inversion layers.

Theory of Tunneling Magnetoresistance

Rigorous theory of the tunneling magnetoresistance (TMR) based on the real-space Kubo formula and fully realistic tight-binding bands fitted to an ab initio band structure is described. It is first applied to calculate the TMR of two Co electrodes separated by a vacuum gap. The calculated TMR ratio reaches 65% in the tunneling regime but can be as high as 280% in the metallic regime when the va...