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http://dx.doi.org/10.7236/JIIBC.2017.17.4.187

Coupling Efficiency of Asymmetric Grating-Assisted Directional Coupler  

Ho, Kwang-Chun (Dept. of Information and Communications Engineering, Hansung University)
Publication Information
The Journal of the Institute of Internet, Broadcasting and Communication / v.17, no.4, 2017 , pp. 187-192 More about this Journal
Abstract
Rigorous longitudinal modal transmission-line theory (L-MTLT) is applied to analyze maximum power transfer in asymmetric grating-assisted directional couplers(A-GADC). By defining a coupling efficiency amenable to rigorous analytical solutions and interference between symmetric and asymmetric supermodes, the power exchange of TE modes as a function of propagation distance is numerically evaluated. The numerical result reveals that maximum power transfer occurs at a grating period ${\Lambda}_{eq}$, in which the insertion loss of supermodes is equal to each other. That is, it is generally different from conventional phase-matching condition of GADC. Furthermore, as the asymmetric profile of grating change to symmetrical profile, the coupling length decreases and the coupling efficiency for power transmission increases.
Keywords
Asymmetric GADC; Coupling efficiency; Supermodes;
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Times Cited By KSCI : 2  (Citation Analysis)
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