二维拓扑材料可饱和吸收体的制备及其超快特性的研究

发布时间：2018-02-22 14:51

本文关键词： 超短脉冲可饱和吸收体二维拓扑材料调Q 锁模碲化锑 Nd:YVO4 Nd:GYSGG　出处：《聊城大学》2017年硕士论文　论文类型：学位论文

【摘要】：在可饱和吸收体(SA)的发展历程中,石墨烯的发现为之后的研究方向提供了一条极具价值的线索,石墨烯的迅猛发展使得类石墨烯材料备受关注。二维拓扑材料如过渡金属二硫属化物(Transition Metal Dichalcogenides TMDs)是典型的类石墨烯材料,它在电学、力学、光学及热学等方向的诸多优势,使得其在各个领域被大量应用。本文主要研究以二维拓扑材料为可饱和吸收体产生超短脉冲的实验即研究它的可饱和吸收特性。产生超短脉冲通常主要通过调Q技和锁模技术来实现,其中被动调Q和被动锁模技术因结构简单、稳定性较好而被常用。可饱和吸收体作为其中不可或缺的调制元件一直备受关注,不断寻找更加优异的SA也成为研究人员的目标,从最初的染料可饱和吸收体、可饱和吸收镜(SESAM),到后来的碳纳米管、石墨烯,直至现今的二维拓扑材料,SA经历了一个漫长的发展史,超短脉冲的产生技术也在不断进步。本课题主要研究内容有:1、论述了课题的研究背景和二维拓扑材料的研究意义及其制备方法;对被动调Q或者说可饱和吸收体的研究进展进行了总结。2、制备了二硫化钼可饱和吸收体,设计了基于它的Nd:GYSGG被动调Q和调Q锁模运转,得到结果:对于被动调Q运转,当泵浦功率为4 W,输出功率为250 mW,光光转换效率6.5%,最短脉冲宽度为833 ns,重复频率为51 kHz;对于调Q锁模运转,当泵浦功率为4 W,最大输出功率为0.167 W,光光转换效率为3.96%,调Q包络中脉冲序列的重复频率为87 MHz,锁模脉冲宽度为260 ps。3、制备了二硫化钨可饱和吸收体,设计了基于它的Nd:GYSGG被动调Q和被动锁模激光器,得到结果:对于被动调Q运转,当泵浦功率为4 W,输出镜分别为15%和27%时,获得最短脉冲分别为620 ns和591 ns,其对应的序列重复频率为67.35kHz和70.7kHz,光光转换效率分别为9.2%和7.5%;对于调Q锁模运转,在泵浦功率为4 W时最大输出功率为0.153 W,光光转换效率为3.22%,调Q包络中脉冲序列的重复频率为78 MHz,锁模脉冲宽度为307 ps。4、制备了碲化锑可饱和吸收体,设计了基于它的Nd:YVO4被动锁模激光器,获得实验结果:调Q锁模时在泵浦功率为2.3 W时最大输出功率为0.119 W,光光转换效率为3.79%,调Q包络中脉冲序列的重复频率为93.85 MHz,锁模脉冲宽度为925ps。
[Abstract]:In the development of saturable absorber SA), the discovery of graphene provides a valuable clue for the future research. The rapid development of graphene has attracted much attention. Two-dimensional topological materials, such as transition Metal Dichalcogenides TMDs, are typical graphene like materials, which have many advantages in electrical, mechanical, optical and thermal fields. In this paper, the experiment of ultrashort pulse produced by two-dimensional topological material as saturable absorber is mainly studied, that is, the characteristic of saturable absorption of ultrashort pulse is studied. The generation of ultrashort pulse is usually by Q-switched. Technology and mode-locking technology to achieve, Among them, passive Q-switching and passive mode-locking techniques are commonly used because of their simple structure and good stability. From the original dye saturable absorber, saturable absorbent mirror, to carbon nanotubes, graphene, and now a two-dimensional topological material, SA, has undergone a long history of development. The generation technology of ultrashort pulse is also improving. The research background of the subject and the research significance of two-dimensional topological material and its preparation method are discussed in this paper. The research progress of passively Q-switched or saturable absorber is summarized. The molybdenum disulfide saturable absorber is prepared. Based on it, the passive Q-switched and Q-switched mode-locking operation of Nd:GYSGG are designed. The results are as follows: for passive Q-switched operation, When the pump power is 4 W, the output power is 250 MW, the optical and optical conversion efficiency is 6.5, the shortest pulse width is 833 ns, the repetition rate is 51 kHz. When the pump power is 4 W, the maximum output power is 0.167 W, the optical and optical conversion efficiency is 3.96, the repetition rate of pulse sequence in Q-switched envelope is 87 MHz, the pulse width of mode-locked pulse is 260 ps.3, the saturable absorber of tungsten disulfide is prepared. A Nd:GYSGG passively Q-switched and mode-locked laser based on it is designed. The results are as follows: when the pump power is 4 W, the output mirror is 15% and 27 respectively for the passive Q-switched operation. The shortest pulses are 620ns and 591ns, respectively, and the corresponding repeat frequencies are 67.35kHz and 70.7kHz. The optical and optical conversion efficiency are 9.2% and 7.5 respectively. When the pump power is 4 W, the maximum output power is 0.153 W, the optical-optical conversion efficiency is 3.22, the repetition rate of pulse sequence in Q-switched envelope is 78 MHz, the pulse width of mode-locked pulse is 307 ps.4, the saturable absorber of antimony telluride has been prepared. A passive mode-locked Nd:YVO4 laser based on it is designed. The experimental results show that the maximum output power is 0.119 W when the pump power is 2.3 W, the optical conversion efficiency is 3.79 and the repetition rate of pulse sequence in Q-switched envelope is 93.85 MHz, and the pulse width of mode-locked pulse is 925 PS.
【学位授予单位】：聊城大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN248

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