Exotic circuit elements from zero-modes in hybrid superconductor/quantum Hall systems

David J. Clarke; Jason Alicea; Kirill Shtengel

doi:10.1038/nphys3114

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arXiv · 1312.6123

Exotic circuit elements from zero-modes in hybrid superconductor/quantum Hall systems

David J. Clarke·Jason Alicea·Kirill Shtengel

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Abstract

Heterostructures formed by quantum Hall systems and superconductors have recently been shown to support widely coveted Majorana fermion zero-modes and still more exotic `parafermionic' generalizations. Here we establish that probing such zero-modes using quantum Hall edge states yields non-local transport signatures that pave the way towards a variety of novel circuit elements. In particular, we demonstrate quite generally that at low energies the zero-modes convert chirally moving quasiparticles into oppositely charged quasiholes propagating in the same direction---that is, they swap the sign of the chiral edge currents. One may then construct new and potentially useful circuit elements using this `perfect Andreev conversion' process, including superconducting current and voltage mirrors as well as transistors for fractional charge currents. Characterization of these circuit elements should provide striking evidence of the zero-mode physics.

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David J. Clarke, Jason Alicea, Kirill Shtengel. 2014-01-15. Exotic circuit elements from zero-modes in hybrid superconductor/quantum Hall systems. https://doi.org/10.1038/nphys3114

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