We report an analysis of the operation of a new type of laser resonator with two-dimensional distributed feedback from a photonic crystal. The gain medium consists of a 2-(4-biphenylyl)-5(4-tert-butylphenyl)-1,3,4-oxadiazole host doped with Coumarin 490 and DCM and is deposited on lithographically patterned Si/SiO2 structures. Bragg reflections caused by the grating diminish the group velocity of photons along some directions of crystallographic symmetry to zero, and the resulting feedback gives rise to laser oscillations. Dispersion relations for photons were calculated analytically and are used to interpret the laser emission spectra.

Optically pumped laser emission has been observed from thin films of 8-hydroxyquinolinato aluminum (Alq) doped with a DCM dye deposited on a diffraction grating formed by imprinting a film of BCB with a mold. The BCB film, which is 4 μm thick, is deposited on a silicon or a flexible plastic substrate. Laser emission occurs at a wavelength near 655 nm which corresponds to the third order of the grating, which has a periodicity of ∼0.6 μm.

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We report on the far-field emission characteristics of two-dimensional photonic crystal-based organic waveguide lasers. The photonic crystals possess square vein, triangular, and honeycomb symmetries. The two-dimensional gratings are fabricated by employing soft lithographic methods. The far-field pattern that we observe is a result of out-of-plane diffractive coupling of the laser emission generated in the plane of the waveguide. This emission pattern offers a convenient and powerful way to evaluate the nature of laser action in such resonators. In devices which possess defects/breaks in the periodicity of the two-dimensional grating, laser emission generated in-plane is scattered in the plane of the waveguide. This phenomenon is the photonic crystal analogue of Kikuchi scattering in electronic crystals.

The Ag2Se/GeSe inorganic photoresist system has been used to produce submicron features by optical lithography. A practical process incorporating this material is the inorganic resist/polymer bilevel scheme. The successful printing of 0.5 μm lines and spaces is explained by the existence of an ’’edge sharpening’’ effect which accompanies the photo-doping process. Conventionally accepted limitations of photolithography are circumvented by the Ag2Se/GeSe resist, whose properties also include high contrast, resistance to O2 plasma, and high absorbance of UV light.