Ultrafast Tm-doped fiber laser system delivering 1.65-mJ, sub-100-fs pulses at a 100-kHz repetition rate

Abstract

High-energy, ultrafast, short-wavelength infrared laser sources with high average power are important tools for industrial and scientific applications. Through the coherent combination of four ultrafast thulium-doped rod-type fiber amplifiers, we demonstrate a Tm-doped chirped pulse amplification system with a compressed pulse energy of 1.65 mJ and 167 W of average output power at a repetition rate of 101 kHz. The system delivers 85 fs pulses with a peak power of 15 GW. Additionally, the system presents a high long- and short-term stability. To the best of our knowledge, this is the highest average output power short wavelength IR, mJ-class source to date. This result shows the potential of coherent beam combining techniques in the short wavelength infrared spectral region for the power scalability of these systems.

132 W, 1.3 mJ, sub-two-cycle pulses at 1.8 μm wavelength

“…1 depicts the experimental setup of the nonlinear compression. The Tm-doped fiber laser system is based on the coherent combination of four Tm-doped rod-type amplifiers [11], which provides 180 W combined average power, sub-90 fs pulse duration, with 1920 nm central wavelength at 101 kHz repetition. In the nonlinear compression stage, the laser output is coupled into a 1.05 m long, rod-type hollow-core fiber (HCF) with a core diameter of 500 µm.…”

“…Another viable approach is via nonlinear compression of ultrafast thulium(Tm)-doped fiber lasers with a broad emission bandwidth around 1.9 µm wavelength. The recent works of ultrafast Tm-doped fiber lasers delivering 1 kW average power [10] or 15 GW pulse peak power [11] emphasizes the power scaling potential of this technology. In this contribution, we present our first results of the nonlinear post compression of an ultrafast Tm-doped fiber laser in a gas-filled capillary.…”

High Average Power Nonlinear Pulse Compression in a Gas-filled Multi-pass Cell at 2 μm Wavelength

“…Another concept aimed at high-power ultrashort pulse generation in the SWIR is based on thulium-doped fiber chirped-pulse amplification systems (Tm:FCPA). These lasers deliver multi-GW peak powers, multi-100 W average output power with pulses as short as sub-100 fs [6]. Nevertheless, a subsequent pulse shortening according to the above discussion is typically desired.…”

100W, 1 mJ, few-cycle pulses at 2 μm wavelength

“…One common method to address the SWIR region is optical parametric chirped pulse amplification (OPCPA), which already demonstrated direct generation of sub 20 fs pulses [5] or more than 100 W average power [6] with mJ-level pulse energies. An alternative method is to post-compress the output of thulium(Tm)-doped fiber laser systems, which have been proven to be a viable approach for power scaling in the SWIR region, reporting 1 kW of average output power [7] or 15 GW of pulse peak power [8] in ultrafast operation. In this contribution, we present our first results of nonlinear post compression of a high-power Tm-doped fiber laser in a gas-filled capillary.…”

“…In this contribution, we present our first results of nonlinear post compression of a high-power Tm-doped fiber laser in a gas-filled capillary. The laser source is based on the coherent combination of four ultrafast Tm-doped fiber amplifiers, delivering a combined pulse energy of 1.67 mJ, with 85 fs pulse duration at a repetition rate of 101 kHz [8]. The post compression stage consists of a 63 cm long rod-type hollow-core fiber with an inner diameter of 350 μm, which is placed on a V-groove inside a high pressure gas vessel filled with ~2 bar of argon.…”