Quantum spin Hall state usually emerges in non-magnetic systems,which are typically incompatible withferromagnetism.Here,we predict that two-dimensional(2D)ferrovalley semiconductor single-layer(SL)2HNbTe_(2)can be tr...Quantum spin Hall state usually emerges in non-magnetic systems,which are typically incompatible withferromagnetism.Here,we predict that two-dimensional(2D)ferrovalley semiconductor single-layer(SL)2HNbTe_(2)can be transformed into a 2D room-temperature quantum spin Hall insulator through hydrogen(H)atom adsorption.The SL 2H-NbTe_(2) is found to possess a giant spontaneous valley polarization of 274 meV,which is much larger than those of most available ferrovalley materials.Upon H atom adsorption,a transitionfrom ferromagnetism to non-magnetism emerges.More interestingly,H-adsorbed NbTe_(2) is predicted to be aquantum spin Hall insulator with a direct band gap of 110meV(equal to a working temperature of 1267 K).The predicted rich quantum effects render the 2H-NbTe_(2) a promising candidate for practical valleytronic andtopological electronics.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.11874092)the Fok Ying Tong Education Foundation,China(Grant No.161005)+2 种基金the Science Fund for Distinguished Young Scholars of Hunan Province(Grant No.2021JJ10039)the Planned Science and Technology Project of Hunan Province(Grant No.2017RS3034)the Postgraduate Scientific Research Innovation Project of Hunan Province(Grant No.CX20240080)。
文摘Quantum spin Hall state usually emerges in non-magnetic systems,which are typically incompatible withferromagnetism.Here,we predict that two-dimensional(2D)ferrovalley semiconductor single-layer(SL)2HNbTe_(2)can be transformed into a 2D room-temperature quantum spin Hall insulator through hydrogen(H)atom adsorption.The SL 2H-NbTe_(2) is found to possess a giant spontaneous valley polarization of 274 meV,which is much larger than those of most available ferrovalley materials.Upon H atom adsorption,a transitionfrom ferromagnetism to non-magnetism emerges.More interestingly,H-adsorbed NbTe_(2) is predicted to be aquantum spin Hall insulator with a direct band gap of 110meV(equal to a working temperature of 1267 K).The predicted rich quantum effects render the 2H-NbTe_(2) a promising candidate for practical valleytronic andtopological electronics.
