Wijnen Frans J P, Berden Giel, Jongma Rienk T
Radboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands.
Opt Express. 2010 Dec 6;18(25):26517-24. doi: 10.1364/OE.18.026517.
We have quantified the sensitivity of a simple method to measure the frequency spectrum of pulsed terahertz (THz) radiation. The THz pulses are upconverted to the optical regime by sideband generation in a zinc telluride (ZnTe) crystal using a continuous wave (cw) narrow-bandwidth near-infrared laser. A single-shot spectral measurement of sideband pulses with a high resolution spectrometer directly provides the spectral information of the THz pulses without the need of adjustable elements in the detection setup. This method has been applied at the free electron laser FELIX, where, for a wavelength of 150 μm (2 THz), pulse trains of 5 μs duration with an integrated energy of 800 nJ, as well as single pulses with an energy as low as 13 nJ could be characterized on a single-shot basis.
我们已对一种用于测量脉冲太赫兹（THz）辐射频谱的简单方法的灵敏度进行了量化。通过使用连续波（cw）窄带宽近红外激光在碲化锌（ZnTe）晶体中产生边带来将太赫兹脉冲上转换到光学波段。利用高分辨率光谱仪对边带脉冲进行单次光谱测量，无需在检测装置中使用可调元件即可直接提供太赫兹脉冲的光谱信息。此方法已应用于自由电子激光FELIX，对于150μm（2 THz）的波长，可在单次测量的基础上对持续时间为5μs、积分能量为800 nJ的脉冲序列以及能量低至13 nJ的单个脉冲进行表征。
