M. Migita et M. Hangyo, Pump-power dependence of THz radiation from InAs surfaces under magnetic fields excited by ultrashort laser pulses, APPL PHYS L, 79(21), 2001, pp. 3437-3439
THz radiation from InAs surfaces excited by ultrashort laser pulses has bee
n studied under low (similar to0.6 muJ/cm(2) fluence) and high (similar to6
mJ/cm(2) fluence) pump power densities. The THz radiation amplitude is aff
ected in both cases. We found that the radiation wave form is broadened by
applying magnetic fields for the low-density-excitation case whereas it is
not for the high-density-excitation case. This result is explained by the d
ifference of the effect of the magnetic field on the THz radiation due to t
he transient photocurrent and optical rectification effects. (C) 2001 Ameri
can Institute of Physics.