Title :
Spectrally Equalized Frequency Comb Generation in Multistage Parametric Mixer With Nonlinear Pulse Shaping
Author :
Ataie, Vahid ; Myslivets, Evgeny ; Kuo, B.P.-P. ; Alic, Nikola ; Radic, Stojan
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of California, San Diego, La Jolla, CA, USA
Abstract :
A novel approach to improve the flatness of wide-band parametric frequency combs is presented. The method relies on nonlinear pulse shaping prior to parametric mixing in a comb-generating device. The parametric comb is generated in a cavity-less multistage shock-wave mixer, using continuous-wave (CW) laser as comb seed. The pulse shaping is accomplished in a regenerative stage incorporating nonlinear optical/amplifying loop mirror (NOLM/NALM) and provides near-ideal seeds for spectrally equalized frequency comb generation in the output mixing stage. The new technique was implemented separately on two comb generators with a coarse (100 GHz) and dense (10 GHz) tone spacing. A 4 dB flatness over 100 nm is achieved with wide-pitched comb, while the fine-pitched device yielded 1500 tones and possessed sub-2 dB spectral flatness over 120 nm bandwidth.
Keywords :
integrated optics; mixers (circuits); nonlinear optics; optical pulse shaping; coarse; comb generators; continuous-wave laser; frequency 100 GHz; multistage parametric mixer; nonlinear optical/amplifying loop mirror; nonlinear pulse shaping; output mixing stage; spectrally equalized frequency comb generation; tone spacing; Chirp; Dispersion; Frequency modulation; Mixers; Nonlinear optics; OFDM; Phase modulation; Parametric process; nonlinear pulse shaping; optical frequency comb;
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2013.2287852