2014/12/25 by Hui Pan, Xin Li, Hua Jiang +2 · 60 citations
Physics and Astronomy · #Computer science #Condensed matter physics #Enhanced Data Rates for GSM Evolution #Geophysics #Magnetic field #Phase (matter) #Physics #Quantum Hall effect #Quantum and electron transport phenomena #Quantum many-body systems #Quantum mechanics #Telecommunications #Topological Materials and Phenomena #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.91.045404
published in Physical Review B 91(4) (American Physical Society)
arxiv created 2014/12/25 · openalex publication_date 2015/01/07 · arxiv updated 2015/06/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate the topological and transport properties of the recently discovered valley-polarized quantum anomalous Hall (VQAH) phase. In a single layer, the phase is realized through the competition between two types of spin-orbit coupling, which breaks the symmetry between the two valleys. We show that the topological phase transition from conventional quantum anomalous Hall phase to the VQAH phase is due to the change of topological charges with the generation of additional skyrmions in the real spin texture, when the band gap closes and reopens at one of the valleys. In the presence of short-range disorders, pairs of the gapless edge channels (one from each valley in a pair) would be destroyed due to intervalley scattering. However, we discover that in an extended range of moderate scattering strength, the transport through the system is quantized and fully valley polarized, i.e., the system is equivalent to a quantum anomalous Hall system with valley-filtered chiral edge channels. We further show that with an additional layer degree of freedom, a much richer phase diagram could be realized with multiple VQAH phases. For a bilayer system, we demonstrate that topological phase transitions could be controlled by the interlayer bias potential.