Enhanced Terahertz Radiation Generation of Photoconductive Antennas Based on Manganese Ferrite Nanoparticles.

This paper presents a significant effect of manganese ferrite nanoparticles (MnFe2 O4 NPs) on the increase of the surface photoconductivity of semiconductors. Herein, the optical characterization of photo-excited carriers of silicon coated with MnFe2 O4 NPs was studied by using THz time-domain spectroscopy (THz-TDs). We observed that silicon coated with MnFe2 O4 NPs provided a significantly enhanced attenuation of THz radiation in comparison with bare silicon substrates under laser irradiation. The experimental results were assessed in the context of a surface band structure model of semiconductors. In addition, photoconductive antennas coated with MnFe2 O4 NPs significantly improved the efficiency of THz radiation generation and signal to noise ratio of the THz signal. This work demonstrates that coating with MnFe2 O4 NPs could improve the overall performance of THz systems, and MnFe2 O4 NPs could be further used for the implementation of novel optical devices.