Related papers: Nonlinear bias dependence of spin-transfer torque …
Based on the time-dependent nonequilibrium Green's function method we investigate theoretically the time and spin-dependent transport through a graphene layer upon the application of a static bias voltage to the electrodes and a…
This work is concerned with the theoretical description of the contrast, i.e., the apparent height difference between two lateral surface positions on constant current spin-polarized scanning tunneling microscopy (SP-STM) images. We propose…
We introduce an orbital dependent electron tunneling model and implement it within the atom superposition approach for simulating scanning tunneling microscopy (STM) and spectroscopy (STS). Applying our method, we analyze the convergence…
We examine transport through a quantum dot coupled to three ferromagnetic leads in the regime of weak tunnel coupling. A finite source-drain voltage generates a nonequilibrium spin on the otherwise non-magnetic quantum dot. This spin…
Current-induced magnetization excitation is a core phenomenon for next-generation magnetic nanodevices, and has been attributed to the spin-transfer torque (STT) that originates from the transfer of the spin angular momentum between a…
Quantum-well (QW) states in {\it nonmagnetic} metal layers contained in magnetic multilayers are known to be important in spin-dependent transport, but the role of QW states in {\it magnetic} layers remains elusive. Here we identify the…
We studied the spin-dependent quantum transport properties using a simple modelling of a Datta-Das spin transistor. We refine previous results by accounting the propagation medium changes of opacity felt by itinerant electrons, when the…
A model of coherent tunneling, which combines multi-orbital tight-binding approximation with Landauer-B\"uttiker formalism, is developed and applied to all-semiconductor heterostructures containing (Ga,Mn)As ferromagnetic layers. A…
We report an unusual, non-monotonous dependence of the exchange bias on the thickness of the ferromagnetic layer in a ferromagnet/antiferromagnet bilayer system. We show that in epitaxial CoO/Fe(110) bilayers, the evolution of the Fe…
We use self-consistent quantum transport theory to investigate the influence of electron-electron interactions on interlayer transport in semiconductor electron bilayers in the absence of an external magnetic field. We conclude that, even…
Recent experiments have revealed nonlinear features of the magnetoresistance in metallic bilayers consisting of a heavy-metal (HM) and a ferromagnetic metal (FM). A small change in the lon- gitudinal resistance of the bilayer has been…
The current dependence of the exponent of the spin torque switching rate of an in-plane magnetized system was investigated by solving the Fokker-Planck equation with low temperature and small damping and current approximations. We derived…
Motivated by the recent experiments of Amasha {\it et al.} [Phys. Rev. B {\bf 78}, 041306(R) (2008)], we investigate single electron tunneling into an empty quantum dot in presence of a magnetic field. We numerically calculate the tunneling…
We fabricate fully epitaxial Fe/ZnO/MgO/Fe magnetic tunnel junctions (MTJs) with a bilayer tunnel barrier, in which ZnO has a metastable rock-salt crystal structure. We observe a high magnetoresistance ratio up to 96% at room temperature…
A three-dimensional self-consistent spin transport model is developed, which includes both tunnelling transport, as well as metallic transport. Using the spin accumulation computed either side of a tunnel barrier, spin torques are obtained,…
The electronic structure and spin-dependent tunneling in epitaxial Fe/MgO/Fe(001) tunnel junctions are studied using first-principles calculations. For small MgO barrier thickness the minority-spin resonant bands at the two interfaces make…
Stochastic magnetic tunnel junctions (s-MTJ) is a promising component of probabilistic bit (p-bit), which plays a pivotal role in probabilistic computers. For a standard cell structure of the p-bit, s-MTJ is desired to be insensitive to…
The ability to switch magnetic elements by spin-orbit-induced torques has recently attracted much attention for a path towards high-performance, non-volatile memories with low power consumption. Realizing efficient spin-orbit-based…
We report on a magnetic field sensor based on CoFeB/MgO/CoFeB magnetic tunnel junctions. By taking advantage of the perpendicular magnetic anisotropy of the CoFeB/MgO interface, the magnetization of the sensing layer is tilted out-of-plane…
Spin transfer torque (STT) driven by a charge current plays a key role in magnetization switching in heavy-metal/ferromagnetic-metal structures. The STT efficiency defined by the ratio between the effective field due to STT and the current…