Chiral Majorana edge modes in anomalous Hall superconductor hybrids · revision history

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Accepted · first revision · record

Title
Chiral Majorana edge modes in anomalous Hall superconductor hybrids
Plain
A quantum anomalous Hall film (a magnetic film with a quantized Hall current at zero field) covered by a superconductor was predicted to carry one-directional Majorana edge channels; a 2017 report of their signature was retracted, and they remain unobserved.
Precise
A magnetic topological insulator film in its quantum anomalous Hall state (Chern number $C = 1$) proximitized by an s-wave superconductor is predicted to enter a topological superconducting phase with Bogoliubov Chern number $N = 1$ and one chiral Majorana edge mode. The 2017 report of the predicted half-quantized two-terminal conductance $0.5 e^{2}/h$ was retracted, and Kayyalha et al. (Science 367, 2020, doi:10.1126/science.aax6361) showed such plateaus arise when the superconductor shorts the device. Determine whether the $N = 1$ phase exists in any such hybrid. An answer is a direct signature, such as thermal Hall conductance $\kappa_{xy} = \kappa_{0}/2$ with $\kappa_{0} = \pi^{2} k_{B}^{2} T/(3h)$, or an interferometric signal of a single chiral Majorana mode.
Settled by
Thermal conductance or Majorana interferometry on a proximitized quantum anomalous Hall edge, with geometries that exclude superconducting shorts.
Kind
well-posed
Answer type
yes-no
References
(empty)
Literature status
open
Status note
No chiral Majorana edge mode is established as of 2026, to this survey's knowledge.
Posed since
2010