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arXiv · 1903.11426

Iterative path-integral summations for the tunneling magnetoresistance in interacting quantum-dot spin valves

S. Mundinar·P. Stegmann·J. König·S. Weiss
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Abstract

We report on the importance of resonant-tunneling processes on quantum transport through interacting quantum-dot spin valves. To include Coulomb interaction in the calculation of the tunneling magnetoresistance (TMR), we reformulate and generalize the recently-developed, numerically-exact method of iterative summation of path integrals (ISPI) to account for spin-dependent tunneling. The ISPI scheme allows us to investigate weak to intermediate Coulomb interaction in a wide range of gate and bias voltage and down to temperatures at which a perturbative treatment of tunneling severely fails.

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S. Mundinar, P. Stegmann, J. König, S. Weiss. 2019-03-27. Iterative path-integral summations for the tunneling magnetoresistance in interacting quantum-dot spin valves. https://doi.org/10.1103/physrevb.99.195457

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