Optimization of DFB Lasing in Chiral Photinic Media
It is known that the most low distributed feedback (DFB) lasing threshold in chiral photinic media (for the definitnes we shall speak below about chiral liquid crystals (CLC)) was observed at the localized mode frequencies (for example at edge mode (EM) frequency). The DFB lasing threshold at the localized mode frequencies in CLCs is rather complicatedly dependent on the CLC and the used in experiments cell parameters. Similar complicated relations exist in the anomalously strong (at the localized mode frequencies) absorption effect revealing themselves, in particular, in the luminescence spectra. Below the results of a theoretical studying of the dependence of the DFB lasing efficiency and the luminescence spectra for CLCs on the relationships of the parameters under discussion are reported. Obtained results explain the experimentally observed non-monotonic dependence of the DFB lasing threshold on the pumping intensity. Options of the experimental observation of the predicted effects are discussed.
Vladimir A Belyakov