Lasing by second-order bragg diffraction in dye-doped POLIPHEM gratings

A composite LC/polymer structure, patented as POLIPHEM, when properly doped with a dye is a promising material for compact tunable laser sources. We analyze the properties of distributed feedback system in a form of volume periodic grating in a medium with gain. The conditions required for lasing threshold achievement are considered for second-order Bragg diffraction regimes. First experimental results on the lasing in POLIPHEM DFB oscillator are reported.