摘要
We investigate the photoinduced resistance change （ΔR/R） in a La0.6Sr0.4MnO3 film （Tc～325 K） at different applied dc currents I （0.1-2.0mA） at 295K. At I = 0.1 mA, we have found a significant photoinduced ΔR/ R 17% under photo-irradiation at excitation energy Eexc=3.05 eV and pump power Ppump =2.5 mJ/cm^2, which has been ascribed to the photo-excited down-spin eg carriers and hence the spin-disorder in the ferromagnetic metallic state. With increasing applied electric current to 2.0 mA, the magnitude of the photoinduced ΔR/ R is reduced to 3%, which may be attributed to current-induced ordering of the localized spins.
We investigate the photoinduced resistance change （ΔR/R） in a La0.6Sr0.4MnO3 film （Tc～325 K） at different applied dc currents I （0.1-2.0mA） at 295K. At I = 0.1 mA, we have found a significant photoinduced ΔR/ R 17% under photo-irradiation at excitation energy Eexc=3.05 eV and pump power Ppump =2.5 mJ/cm^2, which has been ascribed to the photo-excited down-spin eg carriers and hence the spin-disorder in the ferromagnetic metallic state. With increasing applied electric current to 2.0 mA, the magnitude of the photoinduced ΔR/ R is reduced to 3%, which may be attributed to current-induced ordering of the localized spins.
基金
Supported by the National Natural Science Foundation of China under Grant No 10374041, the Program for New Century Excellent Talents in Universities from the Ministry of Education of China under Grant No NECT-04-0456.
