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arXiv · 1712.04359

Phase-locked multi-terahertz electric fields exceeding 13 MV/cm at 190 kHz repetition rate

Matthias Knorr·Jürgen Raab·Maximilian Tauer·Philipp Merkl·Dominik Peller·Emanuel Wittmann·Eberhard Riedle·Christoph Lange·Rupert Huber
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Abstract

We demonstrate a compact source of energetic and phase-locked multi-terahertz pulses at a repetition rate of 190 kHz. Difference frequency mixing of the fundamental output of an Yb:KGW amplifier with the idler of an optical parametric amplifier in GaSe and LiGaS2 crystals yields a passively phase-locked train of waveforms tunable between 12 and 42 THz. The shortest multi-terahertz pulses contain 1.8 oscillation cycles within the intensity FWHM. Pulse energies of up to 0.16 μJ and peak electric fields of 13 MV/cm are achieved. Electro-optic sampling reveals a phase stability better than 0.1 $π$ over multiple hours combined with free CEP tunability. The scalable scheme opens the door to strong-field terahertz optics at unprecedented repetition rates.

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Matthias Knorr, Jürgen Raab, Maximilian Tauer, Philipp Merkl, Dominik Peller, Emanuel Wittmann, Eberhard Riedle, Christoph Lange, Rupert Huber. 2017-12-16. Phase-locked multi-terahertz electric fields exceeding 13 MV/cm at 190 kHz repetition rate. https://doi.org/10.1364/ol.42.004367

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