PbSe量子点光纤的制备及光谱测量【毕业论文】.docxVIP

PbSe 量子点光纤的制备及光谱测量摘要近年来，半导体纳米晶体量子点的研究迅速发展，通过制备不同尺寸和类型的量子点，可以得到不同波长和带宽的吸收和发射谱。研究表明，IV-VI族的中的PbSe量子点的吸收－发射谱覆盖了极宽波带，包括近红外通信的1550nm波段。由于具有波长可调节的特性，PbSe量子点在红外光纤通信器件和激光器件的应用成为了新的研究热点。对于量子点光纤的研究仍有相当多的空白。本文工作如下：（1）利用正己烷、PbSe量子点和紫外固化胶（UV胶）的沸点差异，采用旋转蒸发法，制备了UV胶/PbSe量子点胶体，并稀释得到不同浓度的量子点胶体。通过透射电镜（TEM）、分光光度仪和荧光光谱仪等仪器对PbSe量子点胶体进行了测量和分析。（2）利用压力差，将不同浓度的量子点胶体灌装于孔径为130 ?m的空芯光纤内，并采用紫外固化灯对其固化。进而通过对量子点掺杂光纤（QDF）接口封装、端面抛光等处理后，制备出量子点分布均匀、不同长度和不同浓度的固态纤芯QDF。（3） 采用光功率计和近红外光谱仪分别测量了980nm的泵浦光强度和光致荧光光谱（PL）强度，分析了泵浦光强和荧光光强与QDF的掺杂浓度和光纤长度的关系。I结果表明：直径d=4.4 nm的PbSe QDF，在980 nm波长光的激励下，其吸收系数与掺杂浓度呈线性关系，量子点在UV胶中的吸收截面随浓度近似成e指数减小；PL峰值强度随掺杂浓度和光纤长度变化，找到了最大峰值强度以及对应的掺杂浓度和光纤长度，在浓度为0.4mg.mL-1、QDF长度7 cm时产生了最大光强。通过本文研究表明，制备以UV胶为本底的PbSe QDF，是研发QDF器件的有效途径。关键词：PbSe量子点，PL光谱，UV胶，量子点掺杂光纤，掺杂浓度，光纤长度IIPREPARATION AND SPECTRUM MEASUREMENT OF PbSe QUANTUM-DOT DOPED FIBERSABSTRACTStudies on semiconductor nanocrystal quantum dots (QDs) develop rapidly in recent years. We can obtain variations of emission wavelengths and bandwidths of QDs by controlling the size and type of doped QDs. For IV-VI PbSe QD, the absorption-emission spectra covers a broad wideband, including the near infrared communication band (around 1550 nm). Because of the characteristics of the wavelength can be adjusted, PbSe QD has become a new researching hotspot in the field of infrared optical fiber communication devices and laser devices.This dissertation focuses on preparation and spectrum measurement of the PbSe QDF.The PbSe QD doped UV gel is prepared by using a rotaryIIIevaporation method due to n-hexane, QDs and UV gel with different boiling points. Then, it is diluted to desirable concentrations in the laboratory. We measured the absorption and PL spectra of PbSe QD doped UV gel by using a Transmission Electron Microscopy (TEM), UV-visible Near-infrared Spectrophotometer and Fluorescence Spectrometer, and analyzing the absorption and PL spectra.The QD doped UV gel with various doping concentrations is injected into the hollow fibers in the co