Quantum spin Hall effect in antiferromagnetic topological heterobilayers

The quantum spin Hall (QSH) insulator, ensured by the time-reversal (T) symmetry, has been a conceptual milestone of complex topological phases and well known to realize the quantum anomalous Hall effect when T symmetry is broken by introducing ferromagnetism. Here, based on first-principles calculations and a tight-binding model, we show that, unlike previous T-symmetry breaking, the QSH phase can survive under the antiferromagnetic long-range order in a RbCuSe/CsMnP heterobilayer consisting of a nonmagnetic QSH insulator RbCuSe and an antiferromagnetic insulator CsMnP. The calculated spin Chern number, 22 invariant, and gapless edge state confirm the topological nontrivial phase clearly. Moreover, the role of effective and Rashba spin-orbit coupling and the magnitude of antiferromagnetism are discussed to reveal the underlying physical mechanism. Our results may lead to further scientific and technological advances in topological magnetism and antiferromagnetic spintronics.

Automated summary

The study demonstrates that the QSH phase can survive under antiferromagnetic long-range order in a RbCuSe/CsMnP heterobilayer, exhibiting topological nontrivial features. The role of effective spin-orbit coupling and antiferromagnetism is discussed to reveal the underlying physical mechanism. These findings may lead to advancements in topological magnetism and antiferromagnetic spintronics.