Modeling of polarization effects in Fourier domain mode-locked (FDML) lasers

本计画的目标是模拟傅立叶域锁模光纤腔雷射系统中的偏振效应。这些激光器在宽光谱范围内产生快速频率扫描，满足各种医学成像和传感应用的需要。我们的建议是出于实验证据表明，偏振动力学可以极大地影响输出功率和相干特性。此外，偏振相关应用需要具有受控偏振特性的FDML源。一个例子是偏振敏感光学相干断层扫描，产生关于人体组织的偏振变化特性的深度分辨信息，这可以有助于诊断。详细地说，FDML操作的理论描述，在我们的DFG项目中开发的，将扩展到包括偏振动力学，和一个有效的仿真算法的基础上分步傅立叶方法将被实现。这将使非偏振保持FDML激光器设置，主要用于实际应用中的现实建模。此外，可以分析采用保偏光学元件进行偏振控制的保偏FDML激光器设计中的剩余偏振效应。一个中心目标是发展FDML偏振动力学及其对激光器操作的影响，特别是在非保偏激光器的更好的理解。此外，我们的模拟旨在针对特定应用优化FDML操作，例如输出功率，相干性或偏振特性。

The goal of this project is to model polarization effects in Fourier domain mode locked (FDML) fiber cavity laser systems. These lasers generate fast frequency sweeps over a wide spectral range, as needed for various medical imaging and sensing applications. Our proposal is motivated by experimental evidence that the polarization dynamics can greatly affect the output power and coherence properties. Furthermore, FDML sources with controlled polarization properties are required for polarization dependent applications. One example is polarization sensitive optical coherence tomography, yielding depth-resolved information on polarization changing properties of human tissue, which can be helpful for diagnostics. In detail, the theoretical description of FDML operation, developed in our DFG project, will be extended to include the polarization dynamics, and an efficient simulation algorithm based on the split-step Fourier method will be implemented. This will enable a realistic modeling of non-polarization maintaining FDML laser setups, predominantly used in practical applications. Additionally, residual polarization effects in polarization maintaining FDML laser designs, employing polarization maintaining optical components for polarization control, can be analyzed. A central goal is to develop an improved understanding of FDML polarization dynamics and its influence on laser operation especially in non-polarization maintaining lasers. Furthermore, our simulations aim at an application-specific optimization of FDML operation, for example with respect to output power, coherence or polarization properties.