摘要We investigate the photoinduced effects on the electronic structure for half-metallic ferromagnet CrO2 (Tc～390K), in which the conducting electrons are totally polarized, by using the LSDA+U method. A significant change is found for the band structure and the density of states (DOS) for CrO2 under photo-excitation, especially for the Cr 3dt2g band: disappearance of the spin-split band, suggesting collapse of the half-metallic state. We ascribe the change of electronic structure under photo-excitation to the wider one-electron band W via the strong hybridization of the down-spin Cr 3d and O 2p states. Furthermore we discuss the magnetic properties under photo-excitation.
Abstract：We investigate the photoinduced effects on the electronic structure for half-metallic ferromagnet CrO2 (Tc～390K), in which the conducting electrons are totally polarized, by using the LSDA+U method. A significant change is found for the band structure and the density of states (DOS) for CrO2 under photo-excitation, especially for the Cr 3dt2g band: disappearance of the spin-split band, suggesting collapse of the half-metallic state. We ascribe the change of electronic structure under photo-excitation to the wider one-electron band W via the strong hybridization of the down-spin Cr 3d and O 2p states. Furthermore we discuss the magnetic properties under photo-excitation.
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2007, Vol. 24 
