Генерация импульсов терагерцового излучения в InAs фемтосекундным лазерным возбуждением в присутствии магнитного поля

Abstract

An analytical model describing the effect of a magnetic field on the terahertz pulse generation from InAs surface excited by femtosecond-laser radiation has been proposed. It has been found that the efficiency of terahertz emission grows non-monotonically with increasing magnetic field and may be 5-6 times higher than the efficiency without a magnetic field. As seen from the calculations, photo-emf arises due to a spatial separation of electrons and holes, which are excited by laser pulses and ballistically move from the illuminated surface into the semiconductor bulk, considerably growing with an increase in the external magnetic field; in some hundreds of femtoseconds after the excitation, the photo-emf can reach the values far exceeding the typical ones for the Dember effect.