Femtosecond pulse amplification on a chip
We recently demonstrated a 50x amplification of femtosecond pulses entirely on chip based Thulium as a gain medium. The achieved on-chip peak power levels exceed 800 W at pulse durations of 116fs.
Picture of a chip incorporating multiple amplifier structures.
The amplification of femtosecond pulses is an enabling technology in the investigation of ultrafast phenomena and the synthesis of coherent light across the electromagnetic spectrum, as it provides access to nonlinear optical processes. Translating this technology to the chip level holds significant implications in the implementation of compact and low-cost devices outside of specialized laboratories. However, this advancement has been challenging due to the high intrinsic nonlinearities on chip that occur even during amplification and can compromise the pulse quality dramatically. By carefully managing mode areas and dispersion, we successfully demonstrated a 50x amplification of femtosecond pulses, achieving on-chip peak powers in excess of 800 W and pulse durations of 116 fs. Importantly, this achievement enables the use of typical on-chip femtosecond sources, such as microcombs, modulation combs, and mode-locked lasers, for nonlinear processes without off-chip amplification.
Reference:
Femtosecond pulse amplification on a chip; Mahmoud A. Gaafar, Markus Ludwig, Kai Wang, Thibault Wildi, Thibault Voumard, Milan Sinobad, Jan Lorenzen, Henry Francis, Shuangyou Zhang, Toby Bi, Pascal DeľHaye, Michael Geiselmann, Neetesh Singh, Franz X. Kärtner, Sonia M. Garcia-Blanco, Tobias Herr; arXiv:2311.04758