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arXiv · 2106.14595

Artificial event horizons in Weyl semimetal heterostructures and their non-equilibrium signatures

Christophe De Beule·Solofo Groenendijk·Tobias Meng·Thomas L. Schmidt
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Abstract

We investigate transport in type-I/type-II Weyl semi\-metal heterostructures that realize effective black- or white-hole event horizons. We provide an exact solution to the scattering problem at normal incidence and low energies, both for a sharp and a slowly-varying Weyl cone tilt profile. In the latter case, we find two channels with transmission amplitudes analog to those of Hawking radiation. Whereas the Hawking-like signatures of these two channels cancel in equilibrium, we demonstrate that one can favor the contribution of either channel using a non-equilibrium state, either by irradiating the type-II region or by coupling it to a magnetic lead. This in turn gives rise to a peak in the two-terminal differential conductance which can serve as an experimental indicator of the artificial event horizon.

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Christophe De Beule, Solofo Groenendijk, Tobias Meng, Thomas L. Schmidt. 2021-06-28. Artificial event horizons in Weyl semimetal heterostructures and their non-equilibrium signatures. https://doi.org/10.21468/scipostphys.11.5.095

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