Discovery of Tunable Quantum Anomalous Hall Octet
Bernal bilayer graphene is a naturally occurring system with neither spin-orbit coupling nor moiré complex. •Quantum anomalous Hall (QAH) octet, i.e., eight states exhibiting quantum Hall effect at zero magnetic field, was theoretically predicted and experimentally observed.
Fan Zhang (University of Texas at Dallas)
- Bernal bilayer graphene is a naturally occurring system with neither spin-orbit coupling nor moiré complex.
- Quantum anomalous Hall (QAH) octet, i.e., eight states exhibiting quantum Hall effect at zero magnetic field, was theoretically predicted and experimentally observed.
- Ferromagnetism, ferroelectricity, and QAH effect coexist and cooperate in these competing ground states, thus switchable via magnetic/electric field and carrier sign.
- Bilayer graphene offers a potential platform for quantum information, quantum computing, and quantum sensing.
- Few-layer quasi-1D materials such as Bi4I4 and Bi4Br4have been predicted to be the time-reversal counterpart !