Real-time monitoring of continuous-wave terahertz radiation using a fiber-based, terahertz-comb-referenced spectrum analyzer.
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.
Yasui
Takeshi
T
Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan. t-yasui@me.es.osaka-u.ac.jp
Nakamura
Ryotaro
R
Kawamoto
Kohji
K
Ihara
Atsushi
A
Fujimoto
Yoshihide
Y
Yokoyama
Shuko
S
Inaba
Hajime
H
Minoshima
Kaoru
K
Nagatsuma
Tadao
T
Araki
Tsutomu
T