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An Antisymmetric Berry Frictional Force At Equilibrium in the Presence of Spin-Orbit Coupling

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 نشر من قبل Hung-Hsuan Teh
 تاريخ النشر 2021
  مجال البحث فيزياء
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We analytically calculate the electronic friction tensor for a molecule near a metal surface in the case that the electronic Hamiltonian is complex-valued, e.g. the case that there is spin-orbit coupling and/or an external magnetic field. In such a case, {em even at equilibrium}, we show that the friction tensor is not symmetric. Instead, the tensor is the real-valued sum of one positive definite tensor (corresponding to dissipation) plus one antisymmetric tensor (corresponding to a Berry pseudomagnetic force). Moreover, we find that this Berry force can be much larger than the dissipational force, suggesting the possibility of strongly spin-polarized chemicurrents or strongly spin-dependent rate constants for systems with spin-orbit coupling.



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