Ruchert Clemens, Vicario Carlo, Hauri Christoph P
Paul Scherrer Institute, SwissFEL, 5232 Villigen PSI, Switzerland.
Paul Scherrer Institute, SwissFEL, 5232 Villigen PSI, Switzerland and Ecole Polytechnique Federale de Lausanne, 1015 Lausanne, Switzerland.
Phys Rev Lett. 2013 Mar 22;110(12):123902. doi: 10.1103/PhysRevLett.110.123902.
High-field terahertz (THz) single-cycle pulses with 1.5 MV/cm are generated by optical rectification in the stilbazolium salt crystal 4-N,N-dimethylamino-4'-N'-methyl-stilbazolium 2,4,6-trimethylbenzenesulfonate. We show experimentally that the generated THz transient carrying 5 octaves (0.15 to 5.5 THz) undergoes a complex time-frequency evolution when tightly focused, and we present a model based on three independent oscillating dipoles capable to describe this anomalous field evolution. Finally, we present a method to control the absolute phase of such supercontinuum THz pulses as an essential tool for future field-sensitive investigations.
通过在4-N，N-二甲基氨基-4'-N'-甲基-苯乙烯基苯并噻唑鎓2,4,6-三甲基苯磺酸盐晶体中进行光整流，产生了电场强度为1.5 MV/cm的高场太赫兹（THz）单周期脉冲。我们通过实验表明，所产生的覆盖5个倍频程（0.15至5.5 THz）的太赫兹瞬态信号在紧聚焦时会经历复杂的时频演化，并且我们提出了一个基于三个独立振荡偶极子的模型，该模型能够描述这种异常的场演化。最后，我们提出了一种控制此类超连续太赫兹脉冲绝对相位的方法，作为未来场敏感研究的重要工具。
