The search for novel materials with new functionalities and applications potential is continuing to intensify.Quantum anomalous Hall(QAH)effect was recently realized in magnetic topological insulators(TIs)but only at ...The search for novel materials with new functionalities and applications potential is continuing to intensify.Quantum anomalous Hall(QAH)effect was recently realized in magnetic topological insulators(TIs)but only at extremely low temperatures.Here,based on our first-principles electronic structure calculations,we predict that chemically functionalized Ⅲ-Bi honeycombs can support large-gap QAH insulating phases.Specifically,we show that functionalized AlBi and TlBi films harbor QAH insulator phases.GaBi and InBi are identified as semimetals with non-zero Chern number.Remarkably,TlBi exhibits a robust QAH phase with a band gap as large as 466 meV in a buckled honeycomb structure functionalized on one side.Furthermore,the electronic spectrum of a functionalized TlBi nanoribbon with zigzag edge is shown to possess only one chiral edge band crossing the Fermi level within the band gap.Our results suggest that Ⅲ-Bi honeycombs would provide a new platform for developing potential spintronics applications based on the QAH effect.展开更多
基金support from the National Center for Theoretical Sciences and the Ministry of Science and Technology of Taiwan under Grants Nos.MOST-104-2112-M-110-002-MY3 and MOST-103-2112-M-110-008-MY3the support under NSYSU-NKMU JOINT RESEARCH PROJECT#105-P005 and#106-P005+3 种基金supported by the US Department of Energy(DOE),Office of Science,Basic Energy Sciences grant number DE-FG02-07ER46352(core research)benefited from Northeastern University’s Advanced Scientific Computation Center(ASCC),the NERSC supercomputing center through DOE grant number DE-AC02-05CH11231support(applications to layered materials)from the DOE EFRC:Center for the Computational Design of Functional Layered Materials(CCDM)under DE-SC0012575the Singapore National Research Foundation for support under NRF Award No.NRFNRFF2013-03.
文摘The search for novel materials with new functionalities and applications potential is continuing to intensify.Quantum anomalous Hall(QAH)effect was recently realized in magnetic topological insulators(TIs)but only at extremely low temperatures.Here,based on our first-principles electronic structure calculations,we predict that chemically functionalized Ⅲ-Bi honeycombs can support large-gap QAH insulating phases.Specifically,we show that functionalized AlBi and TlBi films harbor QAH insulator phases.GaBi and InBi are identified as semimetals with non-zero Chern number.Remarkably,TlBi exhibits a robust QAH phase with a band gap as large as 466 meV in a buckled honeycomb structure functionalized on one side.Furthermore,the electronic spectrum of a functionalized TlBi nanoribbon with zigzag edge is shown to possess only one chiral edge band crossing the Fermi level within the band gap.Our results suggest that Ⅲ-Bi honeycombs would provide a new platform for developing potential spintronics applications based on the QAH effect.
