title: Optical fiber-coupled InGaAs-based terahertz time-domain spectroscopy system.
abstract: The successful demonstration of an optical fiber-coupled terahertz time-domain spectroscopy (THz-TDS) system is described in this study. The terahertz output power of the emitter with two optical band rejection filters was 132 nW, which is an improvement of 70% over the output power without any filters. This improvement is due to the suppression of an optical modulated signal that is reverse-generated when an alternating current bias exceeding a certain threshold is applied to the emitter. Under the optimal alignment conditions, the terahertz detector in a fiber-coupled THz-TDS system clearly measured water vapor dips in the free space.
authors.affiliation: THz Photonics Creative Research Center, Electronics and Telecommunications Research Institute (ETRI), Daejeon 305-700, Korea.
authors.forename: Sang-Pil
authors.initials: SP
authors.lastname: Han
authors.forename: Hyunsung
authors.initials: H
authors.lastname: Ko
authors.forename: Namje
authors.initials: N
authors.lastname: Kim
authors.forename: Han-Cheol
authors.initials: HC
authors.lastname: Ryu
authors.forename: Chul Wook
authors.initials: CW
authors.lastname: Lee
authors.forename: Young Ahn
authors.initials: YA
authors.lastname: Leem
authors.forename: Donghun
authors.initials: D
authors.lastname: Lee
authors.forename: Min Yong
authors.initials: MY
authors.lastname: Jeon
authors.forename: Sam Kyu
authors.initials: SK
authors.lastname: Noh
authors.forename: Hyang Sook
authors.initials: HS
authors.lastname: Chun
authors.forename: Kyung Hyun
authors.initials: KH
authors.lastname: Park