Is even-layer MnBi_2Te_4 an axion insulator? · revision history

Revision 2

Accepted · core change · record

Changes against revision 1:

Title · changed
Revision 1: Is even-layer MnBi2Te4 an axion insulator
Revision 2: Is even-layer $\mathrm{MnBi_2Te_4}$ an axion insulator?
Plain · changed
Revision 1: Thin MnBi2Te4 with an even number of layers shows zero Hall resistance and high longitudinal resistance at zero field, which fits an axion insulator but also an ordinary insulator.
Revision 2: Thin $\mathrm{MnBi_2Te_4}$ with an even number of layers shows zero Hall resistance and high longitudinal resistance at zero field, which fits an axion insulator but also an ordinary insulator.
Precise · changed · core
Revision 1: For even-layer MnBi2Te4 in its antiferromagnetic ground state, determine whether $\theta = \pi$, with half-quantized surface Hall conductance $\pm e^{2}/(2h)$ on the top and bottom surfaces, or whether the state is trivial ($\theta = 0$). The zero Hall plateau alone does not discriminate. An answer is an identification from a surface-resolved or theta-sensitive measurement.
Revision 2: For even-layer $\mathrm{MnBi_2Te_4}$ in its antiferromagnetic ground state, determine whether $\theta = \pi$, with half-quantized surface Hall conductance $\pm e^{2}/(2h)$ on the top and bottom surfaces, or whether the state is trivial ($\theta = 0$). The zero Hall plateau alone does not discriminate. An answer is an identification from a surface-resolved or theta-sensitive measurement.
Settled by
Layer-resolved Kerr or Faraday rotation, nonlocal transport, or a magnetoelectric measurement isolating the $\theta = \pi$ response.
Kind
well-posed
Answer type
identification
References
(empty)
Literature status
contested
Status note
(empty)
Posed since
2019

Decisions