Variations in magnetic and electronic properties as a function of uniaxial strain in wurtzite （Ga,Mn）As nanowires （NWs） grown along the [0001] direction were investigated based on density functional theory （DFT）...Variations in magnetic and electronic properties as a function of uniaxial strain in wurtzite （Ga,Mn）As nanowires （NWs） grown along the [0001] direction were investigated based on density functional theory （DFT）. We found that （Ga,Mn）As NWs are half-metal, and the ferromagnetic state is their stable ground state. The magnetism of the NWs is significantly affected by the strain and by the substituent position of Mn impurities. By examining charge densities near the Fermi level, we found that strain can regulate the conductive region of the N-Ws. More interestingly, the size of spin-down band gap of the NWs is tunable by adjusting uniaxial stress, and the NWs can be converted from indirect to direct band gap under tension.展开更多
By using first-principles calculations within the framework of density functional theory,the electronic and magnetic properties of 3d transitional metal（TM） atoms（from Sc to Zn） adsorbed monolayer Ga As nanosheets...By using first-principles calculations within the framework of density functional theory,the electronic and magnetic properties of 3d transitional metal（TM） atoms（from Sc to Zn） adsorbed monolayer Ga As nanosheets（Ga As NSs） are systematically investigated.Upon TM atom adsorption,Ga As NS,which is a nonmagnetic semiconductor,can be tuned into a magnetic semiconductor（Sc,V,and Fe adsorption）,a half-metal（Mn adsorption）,or a metal（Co and Cu adsorption）.Our calculations show that the strong p–d hybridization between the 3d orbit of TM atoms and the 4p orbit of neighboring As atoms is responsible for the formation of chemical bonds and the origin of magnetism in the Ga As NSs with Sc,V,and Fe adsorption.However,the Mn 3d orbit with more unpaired electrons hybridizes not only with the As 4p orbit but also with the Ga 4p orbit,resulting in a stronger exchange interaction.Our results may be useful for electronic and magnetic applications of Ga As NS-based materials.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11004141 and 11174212)the Program for New Century Excellent Talents in University of Ministry of Education of China(Grant No.11-0351)the Scientific Research Starting Foundation for the Returned Overseas Chinese Scholars,Ministry of Education of China
文摘Variations in magnetic and electronic properties as a function of uniaxial strain in wurtzite （Ga,Mn）As nanowires （NWs） grown along the [0001] direction were investigated based on density functional theory （DFT）. We found that （Ga,Mn）As NWs are half-metal, and the ferromagnetic state is their stable ground state. The magnetism of the NWs is significantly affected by the strain and by the substituent position of Mn impurities. By examining charge densities near the Fermi level, we found that strain can regulate the conductive region of the N-Ws. More interestingly, the size of spin-down band gap of the NWs is tunable by adjusting uniaxial stress, and the NWs can be converted from indirect to direct band gap under tension.
基金Project supported by the National Natural Science Foundation of China(Grant No.11174212)
文摘By using first-principles calculations within the framework of density functional theory,the electronic and magnetic properties of 3d transitional metal（TM） atoms（from Sc to Zn） adsorbed monolayer Ga As nanosheets（Ga As NSs） are systematically investigated.Upon TM atom adsorption,Ga As NS,which is a nonmagnetic semiconductor,can be tuned into a magnetic semiconductor（Sc,V,and Fe adsorption）,a half-metal（Mn adsorption）,or a metal（Co and Cu adsorption）.Our calculations show that the strong p–d hybridization between the 3d orbit of TM atoms and the 4p orbit of neighboring As atoms is responsible for the formation of chemical bonds and the origin of magnetism in the Ga As NSs with Sc,V,and Fe adsorption.However,the Mn 3d orbit with more unpaired electrons hybridizes not only with the As 4p orbit but also with the Ga 4p orbit,resulting in a stronger exchange interaction.Our results may be useful for electronic and magnetic applications of Ga As NS-based materials.
