Title :
Evaluation of frequency stability of terahertz waves generated by Mach-Zehnder-modulator-based flat comb generator
Author :
Morohashi, Isao ; Irimajiri, Yoshihisa ; Kumagai, Motohiro ; Sakamoto, Takanori ; Sekine, Norihiko ; Kawanishi, Tetsuyas ; Yasui, Motoaki ; Hosako, Iwao
Author_Institution :
Nat. Inst. of Inf. & Commun. Technol., Koganei, Japan
Abstract :
In order to generate a reference signal used in phase locking of quantum cascade lasers (QCLs) operating in the THz range, we adopted a photonic down-conversion technique. Optical two-tone signals are created by a combination of a Mach-Zehnder-modulator-based flat comb generator (MZ-FCG) and a dispersion-flattened dispersion-decreasing fiber (DF-DDF). THz signals generated from the two-tone signal by using a uni-traveling carrier diode (UTC-PD). We have demonstrated generation of 700 GHz signals, and confirmed that the signal has the C/N ratio of greater than 30 dB and the frequency stability of 10-11 at the averaging time of 1 sec.
Keywords :
Mach-Zehnder interferometers; laser frequency stability; quantum cascade lasers; terahertz wave generation; Mach-Zehnder-modulator; dispersion-flattened dispersion-decreasing fiber; flat comb generator; frequency stability; phase locking; quantum cascade lasers; reference signal; terahertz waves generation; uni-traveling carrier diode; Laser stability; Optical attenuators; Optical device fabrication; Optical fibers; Optical pulse generation; Quantum cascade lasers; dispersion-flattened dispersion-decreasing fiber; optical frequency comb; terahertz wave;
Conference_Titel :
Microwave Photonics (MWP), 2013 International Topical Meeting on
Conference_Location :
Alexandria, VA
DOI :
10.1109/MWP.2013.6724056
