摘要
Photoinduced effects on the transmission and resistivity in wide-bandwidth manganite La0.7Sr0.3MnO3 films （TC= 350 K） have been investigated at various temperatures in the range of 5-470 K by means of the time-resolved pump-probe method. Below To, we have observed a negative transmission change ATM/TM at 2.54eV and a positive resistivity change AR/R under photo-irradiation at excited energy Eexc = 3.20 eV. With temperature approaching to To, the values of ATM/TM and AR/R show a significant reduction. We have ascribed the photoinduced changes on the transmission and resistivity of the La0.7Sr0.3MnO3 film to the charge-ordering fluctuation in the ferromagnetic phase, which is similar to that observed in the narrow-bandwidth La0.7Sr0.3MnO3 films.
Photoinduced effects on the transmission and resistivity in wide-bandwidth manganite La0.7Sr0.3MnO3 films （TC= 350 K） have been investigated at various temperatures in the range of 5-470 K by means of the time-resolved pump-probe method. Below To, we have observed a negative transmission change ATM/TM at 2.54eV and a positive resistivity change AR/R under photo-irradiation at excited energy Eexc = 3.20 eV. With temperature approaching to To, the values of ATM/TM and AR/R show a significant reduction. We have ascribed the photoinduced changes on the transmission and resistivity of the La0.7Sr0.3MnO3 film to the charge-ordering fluctuation in the ferromagnetic phase, which is similar to that observed in the narrow-bandwidth La0.7Sr0.3MnO3 films.
基金
Supported by the National Natural Science Foundation of China under grant No 10374041, the Programme for New Century Excellent Talents in University, the State Education Ministry of China under grant No NECT-04-0456.
