Measurements of magnetization precession are performed for L2_(1) and B2−ordered Co_(2)FeAl_(0.5)Si_(0.5) full Heusler alloy films using the time−resolved magneto-optical Kerr effect technique in the out-of-plan confi...Measurements of magnetization precession are performed for L2_(1) and B2−ordered Co_(2)FeAl_(0.5)Si_(0.5) full Heusler alloy films using the time−resolved magneto-optical Kerr effect technique in the out-of-plan configuration.Dependence of the precession frequency on the external magnetic field can be fitted by the Landau–Lifshitz–Gilbert equation.The chirp parameters are close to each other for the L2_(1) and B2 structures,and decrease with the external magnetic field increasing.The relaxation rate of the B2−ordered film is smaller than that of the L2_(1) one.展开更多
Ultrafast heavy hole-phonon interactions in highly n-doped GaAs have been selectively studied with femtosecond absorption saturation measurements by tuning the pump-probe photon energy just above the doped electron Fe...Ultrafast heavy hole-phonon interactions in highly n-doped GaAs have been selectively studied with femtosecond absorption saturation measurements by tuning the pump-probe photon energy just above the doped electron Fermi edge.A heavy hole-phonon scattering time of~300fs has been measured,which is consistent with that calculated by a numerical model.Accordingly,an optical deformation potential of about 31 eV has been estimated for this highly n-doped sample.展开更多
基金by the National Natural Science Foundation of China under Grant Nos 10874247,50871030 and 10974032the National Basic Research Program of China under Grant No 2009CB929201.
文摘Measurements of magnetization precession are performed for L2_(1) and B2−ordered Co_(2)FeAl_(0.5)Si_(0.5) full Heusler alloy films using the time−resolved magneto-optical Kerr effect technique in the out-of-plan configuration.Dependence of the precession frequency on the external magnetic field can be fitted by the Landau–Lifshitz–Gilbert equation.The chirp parameters are close to each other for the L2_(1) and B2 structures,and decrease with the external magnetic field increasing.The relaxation rate of the B2−ordered film is smaller than that of the L2_(1) one.
基金Supported by the National Natural Science Foundation of China under Grant No.69676015.
文摘Ultrafast heavy hole-phonon interactions in highly n-doped GaAs have been selectively studied with femtosecond absorption saturation measurements by tuning the pump-probe photon energy just above the doped electron Fermi edge.A heavy hole-phonon scattering time of~300fs has been measured,which is consistent with that calculated by a numerical model.Accordingly,an optical deformation potential of about 31 eV has been estimated for this highly n-doped sample.
