Abstract
Since a rigorous theory for THz radiation generated in magnetic field has not yet been constructed, we want to investigate some properties of the radiation to understand the generating mechanism. We first setup the THz emitter sources in our electro-optic (EO) and antenna detection systems respectively and then do some analyses on the waveforms obtained from these systems to prepare for our further researches. We compared the difference between radiations by electric field mechanism and by magnetic field mechanism and find the bandwidth of THz radiation from InAs in magnetic field is wider than that from SI-GaAs in electric filed. In the magnetic field case, the radiation spectrum is influenced not only by magnetic field intensity but also by the collecting position. We also find the quadratic relationship of radiation power dependence on magnetic field intensity as reported by X.-C. Zhang et al. and N. Sarukura et al. As the magnetic intensity growing larger and larger, the radiation distribution is found to be more and more uniform. Beside, the spatial beam profile is measured to be a Gaussian as in the electric case. Furthermore, we have also test several different samples, and this is very helpful for us to understand the underlying physics in this mechanism.