Frequency Comb Generation in WGM Microsphere Based Generators for Telecommunication Applications
Quantum Electronics 2020
Jānis Braunfelds, Rihards Mūrnieks, Toms Salgals, Inga Brice, Tamara Sharashidze, Ilya Lyashuk, Armands Ostrovskis, Sandis Spolītis, Jānis Alnis, Jurģis Poriņš, Vjačeslavs Bobrovs

Optical frequency combs have revolutionized such fields as optical clocks, precise optical frequency references, optical metrology, and it is possible to use them for coherent optical communications. Previously demonstrated spatial resonator-based Kerr frequency combs could be used instead of expensive laser arrays employed in WDM-PON networks, providing power and spectral effective solution. Here we review the frequency comb generation process, main microresonator parameters as FSR and Q-factor, previously used OFC generator parameters and resulting frequency combs, as well as the implementation of OFC for optical data transmission. Additionally, we generated an optical frequency comb in the setup based on tapered fiber and SiO2 microsphere. The generated frequency comb has a frequency spacing of 2 nm or 257 GHz. During the fabrication of tapered fiber from SMF28, we used the transmission signal to control the taper pulling process. The final measured tapered fiber transmission is ~96%. Microsphere WGMR, exhibiting Q-factor at least 2107 is fabricated from an optical fiber with thicker core than SSMF. Moreover, for future experiments, a frequency comb generator based on a free-space setup consisting of lenses, prism, and microsphere is created, and the Q-factor dependence on different distances between prism and microsphere is investigated.


Keywords
Optical frequency comb (OFC), free spectral range (FSR), Q-factor, tapered fiber, SiO2 microsphere resonator
DOI
10.1070/QEL17409
Hyperlink
https://iopscience.iop.org/journal/1063-7818

Braunfelds, J., Mūrnieks, R., Salgals, T., Brice, I., Sharashidze, T., Lyashuk, I., Ostrovskis, A., Spolītis, S., Alnis, J., Poriņš, J., Bobrovs, V. Frequency Comb Generation in WGM Microsphere Based Generators for Telecommunication Applications. Quantum Electronics, 2020, Vol. 50, No. 11, pp.1043-1049. ISSN 1063-7818. e-ISSN 1468-4799. Available from: doi:10.1070/QEL17409

Publication language
English (en)
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