Generation of Ultra-Wideband Terahertz Pulse by Photoconductive Antenna

광전도안테나에 의한 광대역테라헤르츠파의 발생특성

  • 진윤식 (한국전기연구원 전기물리그룹) ;
  • 김근주 (한국전기연구원 전기물리그룹) ;
  • 손채화 (한국전기연구원 전기물리그룹) ;
  • 정순신 (한국전기연구원 전기물리그룹) ;
  • 김지현 (한국전기연구원 전기물리그룹) ;
  • 전석기 (한국전기연구원 전기물리그룹)
  • Published : 2005.06.01

Abstract

Terahertz wave is a kind of electromagnetic radiation whose frequency lies in 0.1THz $\~$10THz range. In this paper, generation and detection characteristics of terahertz (THz) radiation by photoconductive antenna (PCA) method has been described. Using modern integrated circuit techniques, micron-sized dipole antenna has been fabricated on a low-temperature grown GaAs (LT-GaAs) wafer. A mode-locked Ti:Sapphire femtosecond laser beam is guided and focused onto photoconductive antennas (emitter and detector) to generate and measure THz pulses. Ultra-wide band THz radiation with frequencies between 0.1 THz and 3 THz was observed. Terahertz field amplitude variation with antenna bias voltage, pump laser power, pump laser wavelength and probe laser power was investigated. As a primary application example. a live clover leaf was imaged with the terahertz radiation.

Keywords

Terahertz(THz) Radiation;Femtosecond Lase; Photoconductive Antenna;LT-GaAs;Ultra-Wideband Radiation;T-Ray Imaging

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