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Precise knowledge of the structure of ultrashort light pulses simultaneously in space and time is fundamental for their successful applications. To this end, various techniques have been developed that determine the spatio-spectral properties and couplings. Here, we report on a simple, enhanced version of a spatio-spectral metrology approach termed simplified INSIGHT. Furthermore, we compare two commonly used spatio-spectral diagnostic methods ‘HASO multispectral’ and ‘INSIGHT’. As a source, we utilize a non-collinear optical parametric amplifier that supports few-optical-cycle pulses with an artificially introduced spatio-spectral coupling. While both techniques successfully resolve the introduced aberration, each has distinct practical advantages and disadvantages, which we investigate and discuss. Finally, we propose a practical way to assess the correctness of spatio-temporal characterization results.

The field of attosecond physics has expanded significantly in recent years, yet experimental facilities supporting attosecond pump–attosecond probe spectroscopy remain rare. Here, we present a newly constructed beamline for the generation and application of energetic, isolated extreme ultraviolet (XUV) and soft x-ray attosecond pulses via upscaling of high-harmonic generation (HHG) in a gas medium. The fundamental properties of the HHG radiation—energy, beam profile, spectrum, and divergence—are characterized and optimized. The source delivers up to 55 nJ of pulse energy within the Zr window (65–150 eV) with high stability (∼5%–10%) and a divergence of 0.1 mrad. Numerical simulations identify optimal operating conditions consistent with experimental results. Temporal super-resolution of the driving laser is applied, resulting in a broadened spectral continuum. Furthermore, the beamline includes a split-and-delay stage before focusing the HHG radiation to a < 6 μm spot for pump–probe experiments using two distinct focusing optics. Spatially resolved ion microscopy is employed to trace the generated ions at the focus. The presented beamline is designed for nonlinear XUV studies with isolated attosecond pulses.

Ultrahigh peak-power laser systems with pulse durations of tens of femtoseconds are widely used as drivers for compact sources of particles and secondary radiation. Conversely, lasers with shorter (a few femtoseconds) pulse durations and lower peak powers enable the generation of isolated attosecond light pulses to study nature with unparalleled temporal resolution. Here we report an enhanced optical parametric chirped pulse amplifier system that produces light pulses with a peak power of about 100 TW and a pulse duration as short as 4.3 fs with full waveform control. Coherent field synthesis generates a broadband spectrum, spanning from the visible to the near infrared, through three cascaded amplification stages, each housing two optical parametric amplifiers that sequentially boost complementary spectral regions. The resulting light transients are waveform-stabilized to <300 mrad and focused to an intensity of 1021 W cm−2 and exhibit an outstanding high dynamic range in temporal contrast. Together, these characteristics render the system well suited for demanding relativistic laser–plasma experiments. Utilizing temporal super-resolution, the pulses are shortened to sub-4-fs duration. This platform is dedicated to advancing the frontiers of attosecond electron and X-ray sources.

The field of attosecond physics has expanded significantly in recent years, yet experimental facilities supporting attosecond pump attosecond probe spectroscopy remain rare. Here, we present a newly constructed beamline for the generation and application of energetic, isolated extreme ultraviolet (XUV) and soft X-ray attosecond pulses via upscaling of high-harmonic generation (HHG) in a gas medium. The fundamental properties of the HHG radiation energy, beam profile, spectrum, and divergence are characterized and optimized. The source delivers up to 55 nJ of pulse energy within the Zr window (65-150 eV) with high stability (~5-10) and a divergence of 0.1 mrad. Numerical simulations identify optimal operating conditions consistent with experimental results. Temporal super-resolution of the driving laser is applied, resulting in a broadened spectral continuum. Furthermore, the beamline includes a split-and-delay stage before focusing the HHG radiation to a <6 um spot for pump-probe experiments using two distinct focusing optics. Spatially resolved ion microscopy is employed to trace the generated ions at the focus. The presented beamline is designed for nonlinear XUV studies with attosecond isolated pulses.