沸石模板法定向单一手型单壁碳管及功能化碳量子点的激光器研究

The emergence of new carbon materials provides a new opportunity for the development of laser. In the current project, the effect of synthesis parameters will be investigated to synthesize zeolite single crystal with controlled morphology. The ideal zeolite with specific morphology that meets the requirement of the micro laser cavity with whisper gallery mode will be synthesized. By using the organic amine as carbon source, the well-aligned single-walled carbon nanotubes with single chirality and functional carbon quantum dots will be fabricated in the nanochannels of zeolite. To fulfilling the high luminescence efficiency of carbon materials, the methods for fabricating the well-aligned single walled carbon nanotubes with controlled chirality and extremely high functional carbon quantum dots with controlled size will be investigated in detail. The luminescence mechanism of carbon nanotubes and carbon quantum dots will be revealed. The well-aligned carbon nanotubes will be used as saturable absorber for the manipulation of pulsed fiber laser operation state, which will widen the application of pulsed fiber laser. Moreover, the basic mechanism of the switchable laser between Q-switching and mode locking will be revealed. Finally, the micro-nano lasers that based on micro laser cavity of zeolite will be fulfilled by using high luminescence efficiency of carbon nanotubes and carbom quantum dots as the gain medium.

新型碳材料为激光器的研究及应用拓展提供新的契机。本项目拟开展沸石晶体的生长与形貌控制研究，探讨合成参数对沸石晶体生长的影响，制备出符合耳语回廊模式激光腔型的特定形貌沸石晶体。采用沸石模板法，利用孔道内部的有机胺为碳源制备定向小尺寸单一手型单壁碳管和功能化碳量子点。以获得高发光效率碳管及碳量子为目标导向，实现定向碳管的手型控制与碳量子的尺寸控制及高度功能化，探究定向小尺寸单一手型碳管与功能化碳量子的发光机制。运用定向碳管为偏振相关饱和吸收体实现脉冲光纤激光器的运行状态控制，拓宽光纤激光器的应用领域，揭示调Q与锁模之间切换的内在因素。以高发光效率的碳管及碳量子为增益介质，通过沸石晶体的形貌控制得到基于耳语回廊模式的激光腔型，实现碳管和碳量子点微纳激光器。

制备成本低、可宽波段响应、分散性好、光损伤阈值高以及非线性光学参数可控的可饱和吸收体是实现高性能脉冲激光的关键因素，具有重大的科研价值和产业化应用前景。本项目所采用的沸石模板法制备单壁碳管其碳量子点的制备技术为高性能脉冲激光器的发展提供了契机。在AFI沸石晶体的一维纳米孔道内制备了高定向的单壁碳纳米管阵列，这种定向碳管阵列具有偏振吸收特性。利用这种偏振相关的碳管可饱和吸收体，实现了激光运行状态可控掺铒光纤激光器。此种碳管可饱和吸收体可通过偏振控制器来改变其线性吸收大小，从而调控其可饱和吸收体的调制深度，其调制深度可在14%到4.5%范围内改变。在固定的330 mW泵浦功率下，可实现调Q和锁模两种激光脉冲运行状态的切换。调Q脉冲的重复频率和锁模脉冲的脉宽亦可通过光偏振态的改变来实现调节。再者，在此泵浦功率下，当调制深度为4.5%时可得到束缚态孤子分子锁模。利用AEL沸石晶体为模板制备了（2,2）手型单壁碳管，这种小尺寸碳管在去除AEL模板后可自动转变为石墨烯纳米带，从而实现了石墨烯纳米带的简便制备，为石墨烯纳米带的产业化制备提供了基础。利用水热合成的LTA沸石晶体为模板，通过低温碳化孔道内的小分子三丙胺制备了尺寸均一的碳量子点，这种碳量子点可作为性能优良的可饱和吸收体实现掺铒及掺镱脉冲光纤激光器。利用，利用原位碳化AFS沸石沸石筛孔道内的二丙胺制备了尺寸为1.5-4nm的氮掺杂碳量子点。将C-dots@AFS可饱和吸收体置于掺镱光纤激光腔内可实现稳定的调Q掺镱脉冲激光。