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Optimum gain for plasmonic distributed feedback lasers

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 نشر من قبل Alexander Lisyansky
 تاريخ النشر 2016
  مجال البحث فيزياء
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Although nanolasers typically have low Q-factors and high lasing thresholds, they have been successfully implemented with various gain media. Intuitively, it seems that an increase in the gain coefficient would improve the characteristics of nanolasers. For a plasmonic nanolaser, in particular, a distributed-feed-back (DFB) laser, we propose a self-consistent model that takes into account both spontaneous emission and the multimode character of laser generation to show that for a given pumping strength, the gain coefficient has an optimal value at which the radiation intensity is at a maximum and the radiation linewidth is at a minimum.

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