Monolayer MnTe_(2)stabilized as 1 T structure has been theoretically predicted to be a two-dimensional(2 D)ferromagnetic metal and can be tuned via strain engineering.There is no naturally van der Waals(vdW)layered Mn...Monolayer MnTe_(2)stabilized as 1 T structure has been theoretically predicted to be a two-dimensional(2 D)ferromagnetic metal and can be tuned via strain engineering.There is no naturally van der Waals(vdW)layered MnTe_(2)bulk,leaving mechanical exfoliation impossible to prepare monolayer MnTe_(2).Herein,by means of molecular beam epitaxy(MBE),we successfully prepared monolayer hexagonal MnTe_(2)on Si(111)under Te rich condition.Sharp reflection high-energy electron diffraction(RHEED)and low-energy electron diffraction(LEED)patterns suggest the monolayer is atomically flat without surface reconstruction.The valence state of Mn^(4+)and the atom ratio of([Te]:[Mn])further confirm the MnTe_(2)compound.Scanning tunneling spectroscopy(STS)shows the hexagonal MnTe_(2)monolayer is a semiconductor with a large bandgap of~2.78 eV.The valence-band maximum(VBM)locates at theΓpoint,as illustrated by angle-resolved photoemission spectroscopy(ARPES),below which three hole-type bands with parabolic dispersion can be identified.The successful synthesis of monolayer MnTe_(2)film provides a new platform to investigate the 2D magnetism.展开更多
The electron capture processes in collisions of Li3+ion with Li(1s22s)and Li(1s22p0,1)are investigated by using the two-center atomic orbital close-coupling method in the energy range from 0.1 keV/u to 300 keV/u.The i...The electron capture processes in collisions of Li3+ion with Li(1s22s)and Li(1s22p0,1)are investigated by using the two-center atomic orbital close-coupling method in the energy range from 0.1 keV/u to 300 keV/u.The interaction of the active electrons with the target ion is represented by a model potential.The present results for the Li3+–Li(1s22s)system are compared with the available theoretical data and general agreement is obtained for the high collision energies.It is also found that the total and partial electron capture cross sections are sensitive to the initial charge cloud alignment in the low energy region.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11604366,11634007,21872099,and 22072102)the National Natural Science Foundation of Jiangsu Province,China(Grant No.BK 20160397)support from the Youth Innovation Promotion Association of Chinese Academy of Sciences(Grant No.2017370)。
文摘Monolayer MnTe_(2)stabilized as 1 T structure has been theoretically predicted to be a two-dimensional(2 D)ferromagnetic metal and can be tuned via strain engineering.There is no naturally van der Waals(vdW)layered MnTe_(2)bulk,leaving mechanical exfoliation impossible to prepare monolayer MnTe_(2).Herein,by means of molecular beam epitaxy(MBE),we successfully prepared monolayer hexagonal MnTe_(2)on Si(111)under Te rich condition.Sharp reflection high-energy electron diffraction(RHEED)and low-energy electron diffraction(LEED)patterns suggest the monolayer is atomically flat without surface reconstruction.The valence state of Mn^(4+)and the atom ratio of([Te]:[Mn])further confirm the MnTe_(2)compound.Scanning tunneling spectroscopy(STS)shows the hexagonal MnTe_(2)monolayer is a semiconductor with a large bandgap of~2.78 eV.The valence-band maximum(VBM)locates at theΓpoint,as illustrated by angle-resolved photoemission spectroscopy(ARPES),below which three hole-type bands with parabolic dispersion can be identified.The successful synthesis of monolayer MnTe_(2)film provides a new platform to investigate the 2D magnetism.
基金Project supported by the National Key Research and Development Program of China(Grant No.2017YFA0402300)the National Natural Science Foundation of China(Grant No.11774037)+1 种基金International Atomic Energy Agency,China(Grant No.23196/R0)the Science Challenge Project of China(Grant No.TZ2016001)
文摘The electron capture processes in collisions of Li3+ion with Li(1s22s)and Li(1s22p0,1)are investigated by using the two-center atomic orbital close-coupling method in the energy range from 0.1 keV/u to 300 keV/u.The interaction of the active electrons with the target ion is represented by a model potential.The present results for the Li3+–Li(1s22s)system are compared with the available theoretical data and general agreement is obtained for the high collision energies.It is also found that the total and partial electron capture cross sections are sensitive to the initial charge cloud alignment in the low energy region.
