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Dual-mode DFB laser diodes with apodized surface gratings

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Original languageEnglish
Pages (from-to)16303-16314
Number of pages12
JournalOptics Express
Issue number13
Publication statusPublished - Jun 2018
Publication typeA1 Journal article-refereed


Dual longitudinal mode distributed feedback lasers have been fabricated using surface gratings with and without apodization. Analytic formulas and simulations that have been used to derive design guidelines are presented. The fabricated device characteristics are in good agreement with the simulations. The grating apodization enables a lower threshold current density, a higher output power and a broader range of difference frequency tunability by bias, which can be extended beyond the measured 15\&\#x02013;55 GHz by changing the device structure. The apodization and the complex coupling of the surface gratings reduce the effects of the uncontrollable phase of facet reflections, enabling the use of higher facet reflectivities, which leads to narrower intrinsic short time-scale linewidths.

Publication forum classification

Field of science, Statistics Finland