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arXiv · 1006.0498

Coulomb drag between helical edge states

Vladimir A. Zyuzin·Gregory A. Fiete
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Abstract

We theoretically investigate the Coulomb drag between the edge states of two quantum spin Hall systems. Using an interacting theory of the one-dimensional helical edge modes, we show that the drag vanishes at second order in the inter-edge interaction, where it is typically finite in other systems, due to the absence of backscattering within the edges. However, in the presence of a small external magnetic field the drag is finite and scales as the fourth power of the magnetic field, a behavior that sharply distinguishes it from other systems. We obtain the temperature dependence of the drag for regimes of both linear and quadratic edge dispersion in the presence of a finite field.

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Vladimir A. Zyuzin, Gregory A. Fiete. 2010-09-27. Coulomb drag between helical edge states. https://doi.org/10.1103/physrevb.82.113305

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