Quantum Transport with Spin Dephasing: A Nonequilibrium Green's Function Approach
نویسندگان
چکیده
A quantum transport model incorporating spin scattering processes is presented using the non-equilibrium Green's function (NEGF) formalism within the self-consistent Born approximation. This model offers a unified approach by capturing the spin-flip scattering and the quantum effects simultaneously. A numerical implementation of the model is illustrated for magnetic tunnel junction devices with embedded magnetic impurity layers. The results are compared with experimental data, revealing the underlying physics of the coherent and incoherent transport regimes. It is shown that spin scattering processes are suppressed with increasing barrier heights while small variations in magnetic impurity spin-states/concentrations could cause large deviations in junction magnetoresistances.
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