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arXiv · 1902.07767

The $8Pmmn$ borophene sheet: A solid-state platform for space-time engineering

Tohid Farajollahpour·Zahra Faraei·S. A. Jafari
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Abstract

We construct the most generic Hamiltonian of the $8Pmmn$ structure of borophene sheet in presence of spin-orbit, as well as background electric and magnetic fields. In addition to spin and valley Hall effects, this structure offers a framework to conveniently manipulate the resulting "tilt" of the Dirac equation by applying appropriate electric fields. Therefore, the tilt can be made space-, as well as time-dependent. The border separating the low-field region with under-tilted Dirac fermions from the high-field region with over-tilted Dirac fermions will correspond to a black-hole horizon. In this way, space-time dependent electric fields can be used to design the metric of the resulting space-time felt by electrons and holes satisfying the tilted Dirac equation. Our platform offers a way to generate analogues of gravitational waves by electric fields (instead of mass sources) which can be detected in solid state spectroscopies as waves of enhanced superconducting correlations.

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Tohid Farajollahpour, Zahra Faraei, S. A. Jafari. 2019-02-15. The $8Pmmn$ borophene sheet: A solid-state platform for space-time engineering. https://doi.org/10.1103/physrevb.99.235150

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