2020, Witting, T., Furch, F., Osolodkov, M., Schell, F., Menoni, C., Schulz, C.P., Vrakking, M.J.J.

An attosecond pump-probe beamline with 100 kHz repetition rate for coincidence experiments has been developed. It is based on non-collinear optical parametric chirped pulse ampli-cation and delivers 100 µJ sub-4 fs to an high-harmonic generation source. Details on the generation and characterization of isolated attosecond pulses will be presented. © 2019 Published under licence by IOP Publishing Ltd.

2021, Hasse, Kore, Kip, Detlef, Kränkel, Christian

We show that the inscription velocity of fs-laser written structures in YAG crystals can be significantly improved by the use of MHz repetition rates for the writing process. Using a 10 MHz inscription laser, record high writing velocities up to 100 mm/s are achieved. Also, the selective etching process is accelerated using a diluted mixture of 22% H3PO4 and 24% H2SO4. The diluted mixture enables selective etching of up to 9.6 mm long, 1 µm wide and 18 µm high microchannels in 23 days. The etching parameter D of 11.2 µm2/s is a factor of 3 higher than previously reported and the selectivity is even increased by an order of magnitude.

2019, Zhao, Yongguang, Chen, Weidong, Wang, Li, Wang, Yicheng, Pan, Zhongben, Dai, Xiaojun, Yuan, Hualei, Cai, Huaqiang, Zhang, Yan, Bae, Ji Eun, Park, Tae Gwan, Rotermund, Fabian, Loiko, Pavel, Serres, Josep Maria, Mateos, Xavier, Shen, Deyuan, Griebner, Uwe, Petrov, Valentin

Bilayer graphene synthesized by chemical vapor deposition is successfully applied as a saturable absorber (SA) for the passive mode-locking of a Tm,Ho:CLNGG laser at 2093nm. Near transform-limited pulses as short as 70 fs, i.e., 10 optical cycles, are produced at a 89 MHz repetition rate with 69 mW average output power. To the best of our knowledge, these are the shortest pulses ever reported from graphene-SA mode-locked Tm, or Ho-lasers in the 2 µm spectral region, including bulk and fiber lasers.

2021, Suzuki, Anna, Kränkel, Christian, Tokurakawa, Masaki

We present a combined gain media Kerr-lens mode-locked laser based on a Tm:Lu2O3 ceramic and a Tm:Sc2O3 single crystal. Pulses as short as 41 fs, corresponding to less than 6 optical cycles, were obtained with an average output power of 42 mW at a wavelength of 2.1 μm and a repetition rate of 93.3 MHz. Furthermore, a maximum average power of 316 mW with a pulse duration of 73 fs was achieved.