基于光子多重散射实现光放大的随机激光具有低空间相干性和光谱随机的特点，在无散斑成像和安全防伪等领域具有广泛的应用前景。为更好地满足随机激光的应用需求，需灵活调控随机激光的波长及辐射方向。一般情况下，更换增益介质或调节散射颗粒可以实现对随机激光波长的调控；而分子之间的共振能量转移过程为解决上述波长调控问题提供了一种灵活的途径。随机激光器的内在随机性导致随机激光的辐射方向随机，而光纤、波导等光学结构具有良好的导光性，有机地结合光学微纳结构和随机散射微腔为随机激光的辐射方向操控提供了可能。为此，本论文基于R6G与Oxazine染料之间的共振能量转移机制，设计共振能量转移体系的随机散射微腔与光纤侧面耦合的结构，实现了在动量空间颜色可调的环形角谱随机激光器；构建光栅与共振能量转移体系的随机散射微腔的耦合结构，实现了动量空间双色随机激光。本文具体的研究内容如下：

1. 构建了随机微腔与光纤的耦合结构，研究了该耦合结构中R6G与Oxazine染料之间的共振能量转移过程，利用微腔和光纤界面的耦合作用实现了双色环形角谱随机激光辐射。研究发现，在不断增大泵浦功率的过程中，该耦合结构展现出双色荧光、单色随机激光、双色随机激光三种光谱类型。在双色随机激光辐射情况下，通过改变施/受主配比，可以获得辐射波长在563-791 nm区间可调的黄色随机激光和在640-682 nm之间可调的红色随机激光。通过改变泵浦微腔的位置，实现了黄色随机激光、黄-红双色随机激光、红色随机激光的动态调控，并探究了该位置依赖性在信息加密领域的应用。另外，使用黄色随机激光、黄-红双色随机激光、红色随机激光分别对标准光栅样品成像。相较于氦氖激光，实现的环形角谱随机激光作为照明光源，得到的微区成像结果具有更好的边缘锐度，表明其在无散斑全彩成像方面具有良好的应用前景。

2. 构建了亚波长光栅与共振能量转移体系的随机散射微腔的互补双光栅结构，运用有限元分析方法对分布在增益层光栅结构中的本征模式进行研究，发现在Γ 点形成了高Q因子的准BIC模式，并且准BIC模式对应的本征波长与增益层的光栅周期及有效折射率呈线性关系。在此基础上，加工了该互补双光栅结构，实现了动量空间的黄-红双色随机激光。改变施/受主配比，发现当受主分子浓度较低且在小范围内变化时，Γ 处辐射的随机激光的中心波长固定不变，且线宽约2 nm。另外，通过改变光栅周期，实现了对双色随机激光的动量空间光场、光谱、阈值、共振能量转移效率的调控，实验发现动量空间Γ 点中心波长强烈依赖于光栅周期，两者之间呈线性关系，和理论分析结果一致。

Random lasers based on photon multiple scattering to realize optical amplification have the characteristics of low spatial coherence and spectral randomness, and have a wide range of application prospects in the fields of speckle-free imaging and information security. In order to better meet the application requirements of random laser, the wavelength and radiation direction of random laser need to be flexibly regulated. Usually, replacing the gain medium or adjusting the scattering particles can realize the regulation of random laser wavelength; and the resonance energy transfer process between two molecules provides a flexible way to achieve wavelength regulation. The intrinsic randomness of random lasers leads to the random radiation direction, while optical structures such as optical fibers and waveguides have good light guidance, and the combination of optical micro-structures and random scattering microcavity provides the possibility of manipulating the radiation direction of random lasers. To this end, based on the resonant energy transfer (RET) mechanism between R6G and Oxazine dye, this thesis designs the structure of random scattering microcavity of resonant energy transfer system coupled with the side of optical fiber to realize the ring-shaped angle spectrum (AS) random laser with adjustable color in the momentum space; and constructs the coupling structure of grating and random scattering microcavity of RET system to realize the dual-color random laser in the momentum space. The specific research contents of this thesis are as follows:

1. A coupling structure of random microcavity and optical fiber was constructed, and the RET process between R6G and Oxazine dye in the coupling structure was investigated to realize dual -color ring-shaped AS random laser by utilizing the coupling between the microcavity and fiber interface. It is found that the coupling structure radiates three spectral types: dual-color fluorescence, single-color random laser, and dual-color random laser in the process of increasing pump power density. In the case of dual-color random laser radiation, a yellow random laser with a tunable radiation wavelength in the interval of 563-791 nm and a red random laser with a tunable wavelength between 640-682 nm can be obtained by varying the donor/acceptor ratio. By changing the position of the pumped microcavity, the dynamic regulation of the yellow random laser, the yellow-red dual-color random laser, and the red random laser is realized, and the application of this position dependence in the field of information encryption is explored. In addition, a standard grating sample was imaged using a yellow random laser, a yellow-red dual-color random laser, and a red random laser, respectively. Compared with the helium-neon laser, the realized ring-shaped AS random laser as the illumination source gives micro-region imaging results with better edge sharpness, indicating its promising application in speckle-free full-color imaging.

2. A complementary double grating structure coupled with a sub-wavelength grating and a random scattering microcavity in the RET regime is constructed, and the intrinsic modes distributed in the grating structure of the gain layer are investigated by using the finite element analysis method, and it is found that quasi-BIC modes with a high Q factor are formed at Γ, and that the intrinsic wavelengths corresponding to the quasi-BIC modes have a linear relationship with the grating period and the effective refractive index of the gain layer. On this basis, this complementary double grating structure was processed, and realized a yellow-red dual-color random laser in momentum space. By changing the ratio of application/acceptor, it can be found that the center wavelength of the random laser at Γ is fixed and the line width is about 2 nm if the concentration of the acceptor molecule is low and varies in a small range. In addition, the modulation of the momentum-space optical field, spectra, thresholds, and RET efficiencies of the dual-color random laser is achieved by varying the grating period. The finding in experimental is that the center wavelength at the point Γ of the momentum space strongly depends on the grating period. There is a linear relationship between the two, which is consistent with the theoretical analysis.