| Photonic crystal is a new type of artificial dielectric materials with periodic arrangements. The properties of complex spatial dispersion provide novel mechanisms to control the flow of light, which leads to many abnormal phenomena of physics. Photonic crystal offers the possibility of miniaturizing the optical components to a high degree. Some ranges of forbidden frequencies for electromagnetic waves are called photonic band gaps (PBG) that are similar to electrons in semiconductors. One of the basic characteristic properties of photonic crystal is the presence of PBG and photonic localization. At the PBG wavelength, propagation photon is inhibited inside the photonic crystal structure. The integration limit in the future can be seen which is decided by the electronic characteristics. But photonic has advantages that electronics do not have: speed-up, no interaction, etc. Therefore, photonic will act the leading role in the next generation of devices.So, the study of photonic crystal offers many inspiring and fire-new ideas to physicists, chemist, electronic scientists, optical scientists. The properties of photonic crystal can be applied to controlling the light flow in photonic crystal. The application of photonic crystal are fabrication extremely miniature optical devices, such as frequency filters, optical waveguides, nonlinear optical switches, low gain threshold lasers and photonic crystal fiber etc.Along with the emergence of photonic crystal, a new style laser photonic crystal laser has appeared. Photonic crystal can control the propagation of light in laser devices, which improves the feedback in lasers. The characteristic of photonic crystal determines the unique property of photonic crystal laser. The photonic band gap can restrain the spontaneous of laser, so the photonic crystal laser has low gain threshold,furthermore, the photonic crystal laser has the property of little volume and easy to couple with fiber. The photonic crystal laser will have important and extensive applications in optical communication domain in the future.In this thesis the optical pumping organic photonic crystal distributed- feedback laser devices have been designed, fabricated, and characterized by combining computational simulate with test analysis, design of the device will be optimized. This makes a favorable basis on both theory and experiment to design and fabricate the electrical pumping organic photonic crystal DFB laser in the future. The focus of the thesis lies on the laser structures testing and theory analysis.In the respect of preparing the device the SiN photonic crystal plates on SiO2 as the substrate outside are prepared outside. In our super and clean laboratory, first of all, the surface of photonic crystal needs preconditioning, make sure that the surface is clean enough .Then we adopt SD400 multi-origin controlled organic molecular vapor deposition, then the organic molecular will be vaporized to the surface of photonic crystal. The thickness of the organic material must be thick enough that the organic material can overlay all of the holes. Finally we get the organic photonic crystal DFB laser with different organic gain layer thickness as expectation.In the respect of characterizing the device, we adopt the photoluminescence experiment to measure the properties of the devices. Combining with our experiment condition, we make use of the He-Cd laser to emit 325nm ultraviolet (UV) lasing as the CW optical pumping. We measure that the corresponding emitting spectrum to different thickness of organic gain layer, the characteristics of the gain threshold and the far-field.The photonic crystal DFB lasers based SiO2 with organic gain materials have been designed, fabricated and characterized. The device has a layer of SiO2 which is grown on Si as the substrate of the device. And then a periodic honeycomb pattern is etched into the SiO2 layer to create the photonic crystal. The lattice constant is 400nm, the radius is about 130nm. Finally, an organic gain material NPB is deposited on top of the photonic crystal, completely filling the holes of the photonic crystal. When the thickness of organic gain layer is 200nm, the emitting effect is the best, the laser gain threshold is only 0.40 KW/cm2, the Full Wave at Half Maximum (FWHM) of emit peak is only 0.2nm. This property is better than other DFB lasers. The experiment proved that we can fabricate low gain threshold laser by using photonic crystal.Many organic PCDFB lasers reported in the literatures were etched into silica substrate, and their feedback relied on the index contrast between the silica and the organic gain material deposited on top of the photonic crystal. But the index contrast can be only as small as ~0.3. This property is one essential characteristic which is decided by the material. It is difficult to change. We can only choose another material replace SiO2.The design, fabrication, characteristics and theory analysis of the organic one-dimensional photonic crystal distributed feedback laser device was studied. The structure of the device as follows: first a layer of SiO2 grow on Si with thickness about 2μm as the substrate of the device, a layer of high-index material SiN is deposited on a SiO2 substrate with thickness about 272nm. Then a periodic pattern is etched into the higher-index material to create the one-dimensional photonic crystal. The lattice constant is 390nm, the width of the slot is about 90 nm and 140nm, the etching deepness equals to the thickness of high-index material. Finally, an organic gain material is deposited on top of the photonic crystal, completely filling the holes of the photonic crystal. This structure improves the mode confinement in the waveguide formed by the organic material and the higher-index material and increases the index contrast between the photonic crystal layer and the organic material. These results in stronger mode coupling lead to enhanced feedback and hence to smaller devices. When the thickness of organic gain layer is 350nm, the emitting effect is the best, the laser wavelength is about 690nm, the laser gain threshold is only 0.30 KW/cm2 and 0.50 KW/cm2 respective and the Full Wave at Half Maximum (FWHM) of emit peak is 0.5nm and 0.6nm respective. And the smallest angle is about 4。.In the respect of the theory computation we adopt the Transfer Matrix Method (TMM) to compute the reflection and transmission spectrum of the photonic crystal slab, and the numerical methods have been implemented by the Translight software. By analyzing the results we find the reflection and transmission spectrum will change along with the incident angle. The centre of the frequency will move to the high frequency direction. If compare with other one-dimensional photonic crystal, we find that our photonic crystal has a smaller PBG because of the smaller refractive index difference. For this kind of band-edge photonic crystal laser, it isn't necessary working at the PBG but must be satisfied the Bragg Diffraction Equation.The design, fabrication, characteristics and theory analysis of the organic two-dimensional triangle photonic crystal distributed feedback laser device based on SiN was studied. The structure of the device as follows: first a layer of SiO2 grow on Si with thickness about 2μm as the substrate of the device, a layer of high-index material SiN is deposited on a SiO2 substrate with thickness about 270nm. Then a periodic pattern is etched into the higher-index material to create the two-dimensional photonic crystal. The lattice constant is 400nm, the radius of the hole is about 90 nm and 135nm, the etching deepness equals to the thickness of high-index material. Finally, an organic gain material is deposited on top of the photonic crystal, completely filling the holes of the photonic crystal. When the thickness of organic gain layer is 300nm, the emitting effect is the best, the laser wavelength is about 690nm, the laser gain threshold is only 0.38 KW/cm2 and 0.20 KW/cm2 respective and the Full Wave at Half Maximum (FWHM) of emit peak is 0.6nm and 0.9nm respective. And we also have the far-field figure.In the respect of the theory analysis we adopt the Plane Wave Expansion Method (PWE) to compute the band structures of the photonic crystal slab, and the numerical methods have been implemented by the MIT Photonic Bands (MPB) software. 8 plane waves per unit cell length were used to get the band diagram. The calculation of the energy decay rates is performed using a calculation cell that has size of 1a by1a laterally and 9a vertically. The lattice constant a of the photonic crystal is discretized by 20 mesh points. 180 plane waves per unit cell length were used to get the band diagram. By analyzing the band diagram that this kind of band-edge photonic crystal laser doesn't have the complete PBG. But the lasing modes can be found at theГ,M and K points of the irreducible Brillouin Zone. We can calculate the lasing range of the photonic crystal slab by assuming the lattice constant .Then we can make sure of the organic small molecule material to provide the optical gain. We can analyze the basic principle of the laser by using the DFB laser theory. To triangle photonic crystal laser, the lasing modes are more complicated than other traditional DFB lasers.In sum, the organic photonic crystal DFB laser devices have been designed, fabricated, and characterized in this thesis. As we did the aspect jobs that introduced above, the design of the device structure has been optimized, and the detailed structure parameters of the device are supported. Through our long-playing examination explore, we form a consummate system of fabrication techniques and testing instrument, which will establish the foundation of theory and experiment to fabricate electrical pumping organic photonic crystal DFB laser in the future.
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