C. Gaida, M. Gebhardt, F. Stutzki, C. Jauregui, J. Limpert, A. Tünnermann, "Thulium-doped fiber chirped-pulse amplification system with 2 GW of peak power," Opt. Lett. 41 (17), 4130-4133 (2016).
Thulium-doped fibers with ultra large mode-field areas offer new opportunities for the power scaling of mid-IR ultrashort-pulse laser sources. Here, we present a laser system delivering a pulse-peak power of 2 GW and a nearly transform-limited pulse duration of 200 fs in combination with 28.7 W of average power. This performance level has been achieved by optimizing the pulse shape, reducing the overlap with atmospheric absorption lines, and incorporating a climate chamber to reduce the humidity of the atmospheric environment.