title: Real-time monitoring of continuous-wave terahertz radiation using a fiber-based, terahertz-comb-referenced spectrum analyzer.
abstract: We propose a fiber-based, terahertz-comb-referenced spectrum analyzer which has the advantages of being a portable, alignment-free, robust, and flexible apparatus suitable for practical use. To this end, we constructed a 1550-nm mode-locked Er-doped fiber laser whose mode-locked frequency was stabilized precisely by referring to a rubidium frequency standard, and used it to generate a highly stable terahertz (THz) frequency comb in a photoconductive antenna or an electro-optic crystal. By standardizing the THz comb, we determined the frequency accuracy of an active-frequency-multiplier-chain (AFMC) source to be 2.4 x 10(-11). Furthermore, the potential of the THz spectrum analyzer was effectively demonstrated by real-time monitoring of the spectral behavior of the AFMC source and a photomixing source of two free-running CW lasers at adjacent wavelengths.
authors.affiliation: Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan. t-yasui@me.es.osaka-u.ac.jp
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yasui
authors.forename: Ryotaro
authors.initials: R
authors.lastname: Nakamura
authors.forename: Kohji
authors.initials: K
authors.lastname: Kawamoto
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ihara
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Fujimoto
authors.forename: Shuko
authors.initials: S
authors.lastname: Yokoyama
authors.forename: Hajime
authors.initials: H
authors.lastname: Inaba
authors.forename: Kaoru
authors.initials: K
authors.lastname: Minoshima
authors.forename: Tadao
authors.initials: T
authors.lastname: Nagatsuma
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Araki