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

This paper presents a significant effect of manganese ferrite nanoparticles (MnFe₂O₄ NPs) on the increase of the surface photoconductivity of semiconductors. Herein, the optical characterization of photo-excited carriers of silicon coated with MnFe₂O₄ NPs was studied by using THz time-domain spectroscopy (THz-TDs). We observed that silicon coated with MnFe₂O₄ 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 MnFe₂O₄ NPs significantly improved the efficiency of THz radiation generation and signal to noise ratio of the THz signal. This work demonstrates that coating with MnFe₂O₄ NPs could improve the overall performance of THz systems, and MnFe₂O₄ NPs could be further used for the implementation of novel optical devices.