EUROPHOTON 2022

We demonstrate sub-7-fs pulses derived from a carrier-envelope-phase-stabilized Cr:ZnS mode-locked laser. These pulses drive cascaded intra-pulse difference-frequency mixing in a ZGP crystal, leading to multi-octave (0.9 - 12 $\mu$m) coherent pulse synthesis. The resultant single-cycle mid-infrared wave-forms can be shaped by varying the CEP of the driving pulses.

A mode-locked source operating at 1064 nm producing 13 ps pulses with a repetition rate of 276 MHz and output power of 102 mW is demonstrated. It is achieved by two Nd:YVO4 cavities operating at different wavelengths that interact in shared section through a PPRKTP crystal phase-matching for sum-frequency mixing.

We present a single-mode pumped SESAM-modelocked single-cavity GHz dual-comb laser with widely tunable repetition rate difference. This low noise free-running solid-state laser is applied for THz-TDS using photoconductive antennas. We show nanosecond scans with 36 kHz update rate, yielding a 40-dB dynamic range for an integration time of 2 seconds.

We generate mid-infrared ranging from 12 to 35 THz (9 - 25 $\mu$m) via IDFG. Theradiation is directly generated in GaSe by the pulses of an in-house developed KLM Cr:ZnS oscillator. The spectral coverage towards 30 $\mu$m is in reach, which is of interest for ultrafast spectroscopy of solids.

We investigate third harmonic generation (THG) in thin dielectric HfO2 gradient layers experimentally and theoretically. This method allows for the first time to quantify the third and fifth order susceptibility in dielectric layer materials.

We present the post compression of a thulium-doped fiber laser output in a gas-filled multi-pass cell, delivering 51W average power, 35fs pulse duration at 300kHz repetition rate centered at 1940nm wavelength. To the best of our knowledge, this is the highest average-power multi-pass cell post compression in the
short-wave-infrared reported.