English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The van der Waals antiferromagnetic topological insulator MnBi$_2$Te$_4$represents a promising platform for exploring the layer-dependent magnetism andtopological states of matter. Despite the realization of several quantizedphenomena, such as the quantum anomalous Hall effect and the axion insulatorstate, the recently observed discrepancies between magnetic and transportproperties have aroused controversies concerning the topological nature ofMnBi$_2$Te$_4$ in the ground state. Here, we demonstrate the existence of twodistinct types of zero Hall phenomena in few-layer MnBi$_2$Te$_4$. In additionto the robust zero Hall plateau associated with the axion insulator state, anunexpected zero Hall phenomenon also occurs in some odd-number-septuple layerdevices. Importantly, a statistical survey of the optical contrast in more than200 MnBi$_2$Te$_4$ reveals that such accidental zero Hall phenomenon arisesfrom the reduction of effective thickness during fabrication process, a factorthat was rarely noticed in previous studies of 2D materials. Our finding notonly resolves the controversies on the relation between magnetism and anomalousHall effect in MnBi$_2$Te$_4$, but also highlights the critical issuesconcerning the fabrication and characterization of devices based on 2Dmaterials.

Two types of zero Hall phenomena in few-layer MnBi$_2$Te$_4$