Water window soft x-ray source enabled by a 25 W few-cycle 2.2 µm OPCPA at 100 kHz

Optica, Journal Year: 2019, Volume and Issue: 7(2), P. 168 - 168

Published: Dec. 24, 2019

Coherent soft x-ray (SXR) sources enable fundamental studies in the important water window spectral region. Until now, such have been limited to repetition rates of 1 kHz or less, which restricts count and signal-to-noise ratio for a variety experiments. SXR generation at high rate has remained challenging because missing high-power infrared laser drive high-harmonic (HHG) process. Here we present an optical parametric chirped pulse amplifier (OPCPA) centered wavelength 2.2 µm generating 16.5 fs pulses (2.2 oscillation cycles carrier wave) with 25 W average power peak exceeding 14 GW 100 rate. This corresponds highest reported high-repetition-rate long-wavelength systems. The output this OPCPA system was used generate coherent radiation extending beyond 0.6 keV through HHG high-pressure gas cell.

Language: Английский

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Intense infrared lasers for strong-field science

Advances in Optics and Photonics, Journal Year: 2022, Volume and Issue: 14(4), P. 652 - 652

Published: Aug. 31, 2022

The advent of chirped-pulse amplification in the 1980s and femtosecond Ti:sapphire lasers 1990s enabled transformative advances intense laser–matter interaction physics. Whereas most experiments have been conducted limited near-infrared range 0.8–1 μm, theories predict that many physical phenomena such as high harmonic generation gases favor long laser wavelengths terms extending high-energy cutoff. Significant progress has made developing few-cycle, carrier-envelope phase-stabilized, high-peak-power 1.6–2 μm laid foundation for attosecond X ray sources water window. Even longer wavelength are becoming available suitable to study light filamentation, generation, laser–plasma relativistic regime. Long-wavelength sub-bandgap strong-field excitation a wide solid materials, including semiconductors. In limit, bulk crystals also produce high-order harmonics. this review, we first introduce several important scaling laws physics, then describe recent breakthroughs short- (1.4–3 μm), mid- (3–8 long-wave (8–15 μm) infrared technology, finally provide examples applications these novel lasers. Some broadband ultrafast will profound effects on medicine, environmental protection, national defense, because their cover absorption band, molecular fingerprint region, well atmospheric transparent

Language: Английский

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27 W 2.1 µm OPCPA system for coherent soft X-ray generation operating at 10 kHz

Optics Express, Journal Year: 2020, Volume and Issue: 28(6), P. 8724 - 8724

Published: Feb. 25, 2020

We developed a high power optical parametric chirped-pulse amplification (OPCPA) system at 2.1 µm harnessing 500 W Yb:YAG thin disk laser as the only pump and signal generation source. The OPCPA operates 10 kHz with single pulse energy of up to 2.7 mJ duration 30 fs. maximum average output 27 sets new record for an in 2 wavelength region. soft X-ray continuum generated through harmonic this driver can extend around 0.55 keV, thus covering entire water window (284 eV - 543 eV). With repetition rate still enabling pump-probe experiments on solid samples, be used many applications.

Language: Английский

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Table-top optical parametric chirped pulse amplifiers: past and present

Opto-Electronic Advances, Journal Year: 2022, Volume and Issue: 6(3), P. 220046 - 220046

Published: Sept. 30, 2022

The generation of power- and wavelength-scalable few optical cycle pulses remains one the major challenges in modern laser physics. Over past decade, development table-top parametric chirped pulse amplification-based systems was progressing at amazing speed, demonstrating excellent performance characteristics terms duration, energy, peak power repetition rate, which place them front line ultrafast technology. At present, amplifiers comprise a unique class light sources, currently amplify octave-spanning spectra produce carrier-envelope phase-stable, with multi-gigawatt to multi-terawatt powers multi-watt average powers, carrier wavelengths spanning considerable range spectrum. This article gives an overview on state art amplifiers, addressing their relevant scientific technological aspects, provides short outlook practical applications growing field science.

Language: Английский

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Long seed, short pump: converting Yb-doped laser radiation to multi-µJ few-cycle pulses tunable through 2.5–15 µm

Optics Express, Journal Year: 2022, Volume and Issue: 30(8), P. 13009 - 13009

Published: March 17, 2022

We present a setup for generating broadband (up to 1050 cm-1) and broadly tunable (2.5-15 µm) mid-infrared pulses using an Yb-doped femtosecond laser as the pump source. Our scheme, comprising two parametric amplifiers mixing stage, exploits favorable group velocity matching conditions in GaSe pumped at 2 µm directly produce sub-70 fs throughout tuning range without any additional dispersion compensation, while 30-50 pulse durations are achieved with simple compensation by propagation through thin bulk media. The generated have sub-1% short- long-term energy noise, well stable spectral parameters, delivering 0.5-2 W average mid-IR power. expect source be useful various spectroscopic applications mid-IR.

Language: Английский

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Single-Shot Multi-Stage Damage and Ablation of Silicon by Femtosecond Mid-infrared Laser Pulses

Scientific Reports, Journal Year: 2019, Volume and Issue: 9(1)

Published: Dec. 27, 2019

Although ultrafast laser materials processing has advanced at a breakneck pace over the last two decades, most applications have been developed with pulses near-IR or visible wavelengths. Recent progress in mid-infrared (MIR) femtosecond source development may create novel capabilities for material processing. This is because, high intensities required such processing, wavelength tuning to longer wavelengths opens pathway special regime of laser-solid interactions. Under these conditions, due λ2 scaling, ponderomotive energy laser-driven electrons significantly exceed photon energy, band gap and electron affinity can dominantly drive absorption, resulting paradigm shift traditional concepts Irreversible high-intensity MIR interactions are primary interest this connection, but they not systematically studied so far. To address fundamental gap, we performed detailed experimental investigation modifications silicon by single (λ = 2.7-4.2 μm). Ultrafast melting, interaction silicon-oxide surface layer, ablation oxide crystal surfaces were ex-situ characterized scanning electron, atomic-force, transmission microscopy combined focused ion-beam milling, diffractometry, μ-Raman spectroscopy. Laser induced damage thresholds measured as functions wavelength. The theoretical models did reproduce scaling thresholds. disagreement, discuss possible pathways deposition driven field effects characteristic regime.

Language: Английский

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Generation and characterization of isolated attosecond pulses at 100 kHz repetition rate

Optica, Journal Year: 2021, Volume and Issue: 9(2), P. 145 - 145

Published: Dec. 20, 2021

The generation of coherent light pulses in the extreme ultraviolet (XUV) spectral region with attosecond pulse durations constitutes foundation field science. Twenty years after first demonstration isolated pulses, they continue to be a unique tool enabling observation and control electron dynamics atoms, molecules, solids. It has long been identified that an increase repetition rate sources is necessary for many applications atomic molecular physics, surface science, imaging. Although high harmonic (HHG) at rates exceeding 100 kHz, showing continuum cutoff XUV spectrum, was already demonstrated 2013, number photons per insufficient perform characterization via streaking, let alone pump-probe experiment. Here we report on full HHG driven by near-single-cycle kHz. 10 6 target enables streaking experiments through which are determined consist dominant single pulse. These results open door spectroscopy studies 1 or 2 orders magnitude above current implementations.

Language: Английский

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High power, high repetition rate laser-based sources for attosecond science

Journal of Physics Photonics, Journal Year: 2022, Volume and Issue: 4(3), P. 032001 - 032001

Published: May 31, 2022

Abstract Within the last two decades attosecond science has been established as a novel research field providing insights into ultrafast electron dynamics that follows photoexcitation or photoionization process. Enabled by technological advances in laser amplifiers, turn, powerful engine driving development of sources intense pulses. This article focuses on high repetition rate laser-based delivering energy pulses with duration only few optical cycles, for applications science. In particular, power, parametric chirped pulse amplification system is described, which was developed to drive an pump-probe beamline targeting experiments electron-ion coincidence detection at acquisition rates.

Language: Английский

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Efficient, sub-4-cycle, 1-µm-pumped optical parametric amplifier at 10 µm based on BaGa₄S₇

Optics Letters, Journal Year: 2020, Volume and Issue: 45(20), P. 5692 - 5692

Published: Sept. 14, 2020

We report on a {\mu}J-scale mid-infrared optical parametric amplifier (OPA) based the recently developed wide-bandgap orthorhombic crystal, BaGa4S7 (BGS), and directly compare its performance to that of LiGaS2 (LGS) in same OPA setup. The source is single stage amplifying supercontinuum seed pulses with quantum efficiency 29{\%} at an idler wavelength 10 {\mu}m, featuring nominally carrier-envelope phase-stable pulses. As result pumping 1 overall conversion far exceeds traditional schemes OPA's followed by difference frequency generation. Chirp compensation using bulk germanium resulted 126-fs covering 7.6-11.5-{\mu}m spectral range. BGS holds great promise for power scaling due availability larger single-crystal sizes than LGS.

Language: Английский

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Supercontinuum generation and optical damage of sapphire and YAG at high repetition rates

Optics Letters, Journal Year: 2020, Volume and Issue: 45(16), P. 4507 - 4507

Published: July 6, 2020

We have experimentally investigated supercontinuum (SC) generation and the evolution of optical damage in sapphire YAG crystals with 180 fs, 1035 nm pulses from an amplified Yb:KGW laser variable repetition rates, both tight loose focusing conditions. In this Letter, we demonstrate that extinction SC spectrum always correlates occurrence conical third harmonic generation, which readily serves as indication onset in-bulk damage. Damage-related structural changes nonlinear material are also justified by increased intensity large red shift crystal luminescence corresponding to F center emission. The starts shrinking on time scale between seconds minutes varying condition at rate 200 kHz, whereas produces stable performance for several hours least.

Language: Английский

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