摘要
Quantum anomalous Hall effect (QAHE) is a fundamental quantum transport phenomenon in con- densed matter physics. Until now, the QAHE has only been experimentally realized for Cr/V-doped (Bi, Sb)2We3 but at an extremely low observational temperature, thereby limiting its potential appli- cation in dissipationless quantum electronics. By employing first-principles calculations, we study the electronic structures of graphene co-doped with 5d transition metal and boron atoms based on a com- pensated n-p co-doping scheme. Our findings are as follows: i) The electrostatic attraction between the n- and p-type dopants effectively enhances the adsorption of metal adatoms and suppresses their undesirable clustering, ii) Hf-B and Os-B co-doped graphene systems can establish long-range ferro- magnetic order and open larger nontrivial band gaps because of the stronger spin-orbit coupling with the non-vanishing Berry curvatures to host the high-temperature QAHE. iii) The calculated Rashba splitting energies in Re-B and Pt-B co-doped graphene systems can reach up to 158 and 85 meV, re- spectively, which are several orders of magnitude higher than the reported intrinsic spin-orbit coupling strength.
Quantum anomalous Hall effect (QAHE) is a fundamental quantum transport phenomenon in con- densed matter physics. Until now, the QAHE has only been experimentally realized for Cr/V-doped (Bi, Sb)2We3 but at an extremely low observational temperature, thereby limiting its potential appli- cation in dissipationless quantum electronics. By employing first-principles calculations, we study the electronic structures of graphene co-doped with 5d transition metal and boron atoms based on a com- pensated n-p co-doping scheme. Our findings are as follows: i) The electrostatic attraction between the n- and p-type dopants effectively enhances the adsorption of metal adatoms and suppresses their undesirable clustering, ii) Hf-B and Os-B co-doped graphene systems can establish long-range ferro- magnetic order and open larger nontrivial band gaps because of the stronger spin-orbit coupling with the non-vanishing Berry curvatures to host the high-temperature QAHE. iii) The calculated Rashba splitting energies in Re-B and Pt-B co-doped graphene systems can reach up to 158 and 85 meV, re- spectively, which are several orders of magnitude higher than the reported intrinsic spin-orbit coupling strength.
基金
This work was financially supported by the National Key Research and Development Program (Grant No. 2017YFB0405703), the National Natural Science Foundation of China (Grant Nos. 11104173, 61434002, and 51025101) and Sanjin Scholar of Shanxi. X. D. and Z. Q. also acknowledge the support of the China Government Youth 1000-Plan Talent Program and the National Key Research and Development Program (Grant No. 2016YFA0301700). We are grateful to the supercomputing service of AM-HPC and the Supercomputing Center of USTC for provid- ing the high-performance computing resources used in this study.