Operating characteristics of near-infrared self-assembled polymer microlasers

We report near-infrared laser emission from self-assembled luminescent polymer microcavities. The microrings are formed around silica optical fibers of varying diameters (80, 125, and 200 microm) and are shown to exhibit photopumped lasing at approximately 820 nm. The microrings with 200 mum inner diameter have an overall quality factor of approximately 2 x 10(3), which is limited by surface roughness and scattering. We illustrate how the laser threshold varies inversely with both the quality factor and the diameter of the microrings. The free spectral range and the intensity variation of the laser output are also presented.