Motivation: THz emitter

There has been increasing interest in utilizing terahertz (THz) radiation to information and communications technology, security and safety, biomedical diagnostics, nondestructive evaluation, and quality control. Photoconductive antennas, consisting of metallic antennas patterns fabricated on semiconductor, first appeared in 1984 and then become the most widely used device for THz pulse generation and detection in both laboratories and commercial THz time domain spectroscopy (TDS) system.

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Project: high-efficient photoconductive antenna modeling and design 

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THz photoconductive emitter

Designed antennas for THz pulse radiation from photoconductor switch with bias voltage controlled by a femtosecond laser. A novel approach is proposed for the design of THz dipole, bow tie, and fractal antennas. Based on a full-wave model simulation, the THz radiated power and center frequency using separation design can be largely increased by using a resonant antenna structure instead of the traditional traveling wave antenna structure.

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Full-wave model for photoconductive antenna

H-fractal antenna performance improvement

Sierpinski-fractal antenna performance improvement

Representative Journal Publications:

  1. J. Diao, F. Yang, Z. P. Nie, J. Ouyang, and P. Yang. "Separated fractal antennas for improved emission performance of terahertz radiations." Journal of Electromagnetic Waves and Applications, vol. 26, no. 8-9, pp. 1158-1167, Jun. 2012.

  2. J. Diao, F. Yang, L. Du, J. Yang, and P. Yang. "Enhancing terahertz radiation from dipole photoconductive antenna by blending tips." Progress in Electromagnetics Research Letters, vol. 25, pp. 127-134, 2011.

  3. J. Diao, L. Du, J. Ouyang, P. Yang, and Z. P. Nie. "Enhanced center frequency of terahertz pulse emission from photoconductive antenna". Journal of Electromagnetic Waves and Applications, vol. 25, no. 16, pp. 2236-2243, 2011.