National Synchrotron Light Source, Brookhaven National Laboratory, Upton, New York 11973, USA.
Phys Rev Lett. 2009 Oct 9;103(15):154801. doi: 10.1103/PhysRevLett.103.154801. Epub 2009 Oct 7.
We report the first experimental characterization of efficiency and spectrum enhancement in a laser-seeded free-electron laser using a tapered undulator. Output and spectra in the fundamental and third harmonic were measured versus distance for uniform and tapered undulators. With a 4% field taper over 3 m, a 300% (50%) increase in the fundamental (third harmonic) output was observed. A significant improvement in the spectra with the elimination of sidebands was observed using a tapered undulator. The experiment is in good agreement with predictions using the MEDUSA simulation code.
我们报告了首例使用锥形波荡器对激光种子自由电子激光的效率和光谱增强进行实验特性描述。在均匀和锥形波荡器中，我们测量了基频和三次谐波随距离的输出和光谱。在 3 米范围内有 4%的场锥度，基频（三次谐波）输出增加了 300%（50%）。使用锥形波荡器，观察到光谱得到了显著改善，消除了边带。该实验与使用 MEDUSA 模拟代码的预测结果非常吻合。
