The parameter dynamics of super-sech and super-Gaussian pulses for the perturbed nonlinear Schrödinger’s equation with power-law nonlinearity is obtained in this article. The variational principle successfully recovers this dynamical system. The details of the variational principle with the implementation of the Euler–Lagrange’s equation to the nonlinear Schrödinger’s equation with power-law of nonlinearity described in this paper have not been previously reported.

简述了用于分析多胞超导射频腔场平坦度调节的微扰理论，推导了场平坦度的理论计算方法。针对超导腔微小范围内的纵向拉伸/挤压，进行理论计算分析与结构-电磁多物理场模拟计算以求得变形前后腔体场平坦度及其变化趋势，所得结果表明：理论分析结果与仿真计算结果基本一致，进一步深入验证了该微扰理论的有效性。在多胞超导射频腔的加工制造、运行过程中的关键环节，国际上广泛采用的两种方法——包括预调谐过程中的“先单胞后整腔”和运行时腔体调谐过程中“整腔拉伸/挤压”方法，基于分析结果，这两种方法正确性和合理性均在理论上得以验证。在超导射频腔腔型设计的第一阶段——单胞优化设计过程中加入结构-电磁多物理场分析，可使腔型优化设计过程更加高效，结果表明：优化后的单胞（包括端胞和中间胞）的频率敏感度应尽可能接近或相等，以保证在腔变形期间始终保持较好的场平坦度。

Ultra-high spectral purity lasers are of considerable research interests in numerous fields such as coherent optical communication, microwave photonics, distributed optical fiber sensing, gravitational wave detection, optical clock, and so on. Herein, to deeply purify laser spectrum with compact size under normal condition, we propose a novel and practical idea to effectively suppress the spontaneous radiation of the laser cavity through weak external distributed perturbation. Subsequently, a laser configuration consisting of a main lasing cavity and an external distributed feedback cavity is proposed. The feedback signal with continuous spatio-temporal phase transition controlled by a distributed feedback structure is injected into the main cavity, which can deeply suppress the coupling rate from the spontaneous radiation to the stimulated emission and extremely purify the laser spectrum. Eventually, an ultra-narrow linewidth on-chip laser system with a side mode suppression ratio greater than 80 dB, an output linewidth of 10 Hz, and a relative intensity noise less than -150 dB/Hz is successfully obtained under normal conditions. The proposed concept in this work provides a new perspective for extreme regulation of laser parameters by using weak external distributed perturbation, which can be valid for various gain-type lasers with wide wavelength bands.

为了解决具有强扰动的大型气候环境试验舱温度数据波动大、难以精确控制的问题，本文分析了试验舱温度结构组成、温度控制特点和热负荷扰动来源，提出了适用于大型试验舱温度精确控制的冷热端温度动态模糊PID协调控制算法，研究其控制原理及具体算法。同时提出了利用卡尔曼（Kalman）滤波的温度数据处理方法和基于艾伦（Allan）方差分析的控制效果评判方法。实验结果表明，Kalman 滤波可有效去除温度测量数据中热负荷扰动产生的偏差，更真实反映温度实际变化。本文研究的控制算法相较于传统PID控制算法其温度波动性较小、系统稳态响应时间较短，可以用于大型气候环境试验舱的温度精确控制。

We introduce a formalism, inspired on the perturbation theory for nearly free electrons in a solid-state crystal, to describe the resonances in optical ring resonators subjected to a perturbation in their dielectric profile. We find that, for small perturbations, degenerate resonant modes are split with the splitting proportional to one specific coefficient of the Fourier expansion of the perturbation. We also find an expected asymmetry in the linewidths (and Q factors) of the split modes. Experimental transmission spectra from rings with specially designed perturbations show a qualitative match with the formalism predictions.

Hybrid聚束-加速结构是把驻波预聚束器、行波聚束器和标准加速管集成到一起的新型RF结构。简述了对S波段Hybrid聚束-加速结构样机的束流动力学优化和微波设计结果，解释了Hybrid结构导致发射度增长的原因，对此样机进行了射频低功率测试。样机的冷测结果与RF设计结果一致性很好。在冷测频率2 855.21 MHz处，实测S₁₁小于?45 dB，腔间相移偏差小于±2°，VSWR≤1.2对应的带宽大于5 MHz，轴向场分布完全满足动力学要求。