A5003640749- Laser-Matter Interactions and Applications
- Advanced Fiber Laser Technologies
- Mass Spectrometry Techniques and Applications
- Laser-Plasma Interactions and Diagnostics
- Advanced Electron Microscopy Techniques and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Spectroscopy and Laser Applications
- Scientific Measurement and Uncertainty Evaluation
- Force Microscopy Techniques and Applications
- Photonic Crystal and Fiber Optics
- Advanced Chemical Physics Studies
- Advanced Frequency and Time Standards
- Integrated Circuits and Semiconductor Failure Analysis
Max Planck Institute for Nuclear Physics
2020-2024
European Organization for Nuclear Research
2024
Physikalisch-Technische Bundesanstalt
2021
Wuhan Institute of Physics and Mathematics
2021
Chinese Academy of Sciences
2021
Heidelberg University
2020
Leibniz University Hannover
2016
We have developed an extreme ultraviolet (XUV) frequency comb for performing ultra-high precision spectroscopy on the many XUV transitions found in highly charged ions (HCI). Femtosecond pulses from a 100 MHz phase-stabilized near-infrared are amplified and then fed into femtosecond enhancement cavity (fsEC) inside vacuum chamber. The low-dispersion fsEC coherently superposes several hundred incident and, with single cylindrical optical element, fully compensates astigmatism at $w_0=15\mu$m...
We present a compact closed-loop recycling system for noble and inert gases. It has been developed an extreme-ultraviolet (XUV) frequency comb based on high-harmonic generation at 100 MHz repetition rate. The collects gas injected several bars of backing pressure through micrometer-sized nozzle into the laser-interaction region with differential pumping comprising turbomolecular pumps, subsequently compresses to up 200 bar. By drastically reducing waste expensive gases such as xenon krypton,...
We present a compact velocity-map imaging (VMI) spectrometer for photoelectron at 100 MHz repetition rate. Ultrashort pulses from near-infrared frequency comb laser are amplified in polarization-insensitive passive femtosecond enhancement cavity. In the focus, multi-photon ionization (MPI) of gas-phase atoms is studied tomographically by rotating polarization. demonstrate functioning VMI reconstructing angular momentum distributions xenon MPI. Our intra-cavity setup collects electron energy...
We present a novel ultrastable superconducting radio-frequency (RF) ion trap realized as combination of an RF cavity and linear Paul trap. Its quadrupole mode at 34.52 MHz reaches quality factor $Q\approx2.3\times 10^5$ temperature 4.1 K is used to radially confine ions in ultralow-noise pseudopotential. This concept expected strongly suppress motional heating rates related frequency shifts which limit the ultimate accuracy achieved advanced traps for metrology. Running with its...
We raise the power from a commercial 10 W frequency comb inside an enhancement cavity and perform multi-photon ionization of gas-phase atoms at 100 MHz for first time, to best our knowledge. An intra-cavity velocity-map-imaging setup collects electron-energy spectra xenon rates several orders magnitude higher than those conventional laser systems. Consequently, we can use much lower intensities ${\sim}{{10}^{12}} \;{\rm W}/{{\rm cm}^2} $∼1012W/cm2 without increasing acquisition times above...
Velocity-map imaging (VMI) is a key tool for studying outgoing electrons or ions following optical strong-field interactions of atoms and molecules provides good momentum resolution even if the source volume fragments extends along laser beam path. Here, we demonstrate within an enhancement cavity how, independently focal Rayleigh length, counter-propagating pulses longitudinally compress ionization down to few tens micrometers. We observe nonlinear above-threshold (ATI) processes confined...
Abstract Optical standing waves are intrinsically nanometric, spatially fixed interference-field patterns. At a commensurate scale, metallic nanotips serve as coherent, atomic-sized electron sources. Here, we explore the localized photofield emission from tungsten nanotip with transient wave. It is generated within an optical cavity counter-propagating femtosecond pulses near-infrared, 100-MHz frequency comb. Shifting phase of wave at tip reveals its nodes and anti-nodes through strong...
We report a novel breakup scenario of ultra-short high-order solitons in optical waveguides, via formation shock far below subcycle level, followed by dramatic and complete transition into dispersive wave.
When atoms are exposed to intense laser fields, the Coulomb potential of these is perturbed by high electric field strengths. It results in highly nonlinear effects, such as multi-photon ionization (MPI) or high-harmonic generation (HHG) [1], [2]. To reach required intensities, chirped-pulse amplification at kilohertz repetition rates typically employed [3].
Highly charged ions (HCIs) are promising candidates for measuring the variation of natural constant <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\alpha$</tex> or realizing new frequency standards[1], thanks to their insensitivity external electric fields and ultra-narrow fine-structure transitions. In HCIs, electronic transitions outer electron shifted into extreme ultraviolet (XUV), even X-ray region. Lasers that can drive these not...
Femtosecond enhancement cavities for frequency combs are a powerful tool to study nonlinear processes at high repetition rates. The transfer of the coherence shorter wavelengths by high-harmonic generation (HHG) enabled development in extreme ultraviolet (XUV), with promising prospects precision spectroscopy [1]. However, HHG is not only process which can be investigated. Other phenomena, such as multi-photon ionization (MPI), above-threshold (ATI), or excitation metastable states benefit...
Highly charged ions (HCI) have a few tightly bound electrons and many interesting properties for probing fundamental physics developing new frequency standards. Many optical transitions of HCI are located in the extreme ultraviolet (XUV) conventional light sources do not allow to study these transistions with highest precision. For this reason, we an XUV comb by transfering coherence stability near infrared means high-harmonic generation (HHG). Reaching intensity levels necessary HHG 10 <sup...