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arXiv · 2201.03265

Gas-plasma based generation of broadband THz radiation with 640 mW average power

Joachim Buldt·Henning Stark·Michael Mueller·Christian Grebing·Cesar Jauregui·Jens Limpert
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Abstract

We present a high-power source of broadband terahertz radiation covering the whole THz spectral region (0.1-30 THz). The two-color gas plasma generation process is driven by a state-of-the-art Ytterbium fiber chirped pulse amplification system based on coherent combination of 16 rod-type amplifiers. Prior to the THz generation, the pulses are spectrally broadened in a multi-pass-cell and compressed to 37 fs with a pulse-energy of 1.3 mJ at a repetition rate of 500 kHz. A gas-jet scheme has been employed for the THz generation, increasing the efficiency of the process to 0.1%. The air-biased-coherent-detection scheme is implemented to characterize the full bandwidth of the generated radiation. A THz average power of 640 mW is generated, which is the highest THz average power achieved to date. This makes this source suitable for a variety of applications, e.g. spectroscopy of strongly absorbing samples or driving nonlinear effects for the studies of material properties.

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Joachim Buldt, Henning Stark, Michael Mueller, Christian Grebing, Cesar Jauregui, Jens Limpert. 2022-01-10. Gas-plasma based generation of broadband THz radiation with 640 mW average power. https://doi.org/10.1364/ol.442374

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