相关论文: Spin-flip induced magnetoresistance in positionall…
A recently introduced percolative theory of unipolar organic magnetoresistance is generalized by treating the hyperfine interaction semiclassically for an arbitrary hopping rate. Compact analytic results for the magnetoresistance are…
A recent theory of magnetoresistance in positionally disordered organic semiconductors is extended to include exchange and dipolar couplings between polarons. Analytic results are discovered when the hyperfine, exchange, and dipolar…
The correlation kinetic equation approach is developed that allows describing spin correlations in a material with hopping transport. The quantum nature of spin is taken into account. The approach is applied to the problem of the bipolaron…
In this review, we outline the important results on the resistivity encountered by an electron in magnetically ordered materials. The mechanism of the collision between the electron and the lattice spins is shown. Experiments on the spin…
Spin resistivity $R$ has been shown to result mainly from the scattering of itinerant spins with magnetic impurities and lattice spins. $R$ is proportional to the spin-spin correlation so that its behavior is very complicated near and at…
We predict that singly-occupied carrier traps, produced by electrical stress or irradiation within organic semiconductors, can cause spin blockades and the large room-temperature magnetoresistance known as organic magnetoresistance. The…
We study the effects of spin-flip scatterings on the time-dependent transport properties through a magnetic quantum dot attached to normal and ferromagnetic leads. The transient spin-dynamics as well as the steady-state tunneling…
The charge and spin diffusion equations taking into account spin-flip and spin-transfer torque were numerically solved using a finite element method in complex non-collinear geometry. This approach was used to study the spin-dependent…
Processes which flip the spin of an electron tunneling in a junction made up of magnetic electrodes are studied. It is found that: i) Magnetic impurities give a contribution which increases the resistance and lowers the magnetoresistance,…
We derive the kinetic equations for polaron hopping in organics that explicitly take into account the double occupation possibility and pair intersite correlations. The equations include simplified phenomenological spin dynamics and provide…
The resistivity in magnetic materials has been theoretically shown to depend on the spin-spin correlation function which in turn depends on the magnetic-field, the density of conduction electron, the magnetic ordering stability, etc.…
We develop a theory of magnetoresistance based on variable-range hopping. An exponentially large, low-field and necessarily positive magnetoresistance effect is predicted in the presence of Hubbard interaction and spin-dynamics under…
The propensity of some materials and multilayers to have a magnetic field dependent resistance, called magnetoresistance, has found commercial applications such as giant magnetoresistance harddisk read heads. But magnetoresistance can also…
A theory is introduced for spin relaxation and spin diffusion of hopping carriers in a disordered system. For disorder described by a distribution of waiting times between hops (e.g. from multiple traps, site-energy disorder and/or…
The effect of undesirable high-frequency free-layer switching in magnetic multilayer systems, referred to as back hopping, is investigated by means of the spin-diffusion model. A possible origin of the back-hopping effect is found to be the…
In hopping magnetoresistance of doped insulators, an applied magnetic field shrinks the electron (hole) s-wave function of a donor or an acceptor and this reduces the overlap between hopping sites resulting in the positive magnetoresistance…
We present a theory of organic magnetoresistance (OMR) based on the quenching of the quantum correlation between the carrier's spin and its local environment when the incoherent hopping takes place. We prove that this process contributes a…
In disordered systems, the hopping conductivity regime is usually realized at low temperatures where spin-related phenomena differ strongly from the case of delocalized carriers. We develop the unified microscopic theory of current induced…
Theory of weak localization in two-dimensional high-mobility semiconductor systems is developed with allowance for the spin-orbit interaction. The obtained expressions for anomalous magnetoresistance are valid in the whole range of…
We derive kinetic equations describing injection and transport of spin polarized carriers in organic semiconductors with hopping conductivity via an impurity level. The model predicts a strongly voltage dependent magnetoresistance, defined…