Soft x-ray laser spectroscopy on trapped highly charged ions at FLASH

Area of Science:

• Atomic Physics
• X-ray Science
• Quantum Electrodynamics (QED)

Background:

• Highly charged ions are crucial for testing fundamental physics theories.
• Spectroscopic studies of these ions require high-resolution, high-intensity light sources.
• Existing techniques face limitations in precision and energy range.

Purpose of the Study:

• To demonstrate high-resolution resonant laser excitation of Li-like Fe23+ ions in the soft x-ray region.
• To establish a new technique for high-precision spectroscopy of highly charged ions.
• To pave the way for fundamental insights into QED using advanced x-ray lasers.

Main Methods:

• Utilized ultrabrilliant light from the Free Electron Laser in Hamburg (FLASH).
• Employed an electron beam ion trap to confine Li-like Fe23+ ions.
• Performed resonant laser excitation at 48.6 eV, targeting the 2S(1/2) to 2P(1/2) transition.

Main Results:

• Successfully demonstrated high-resolution resonant laser excitation at 48.6 eV.
• Achieved excitation of Li-like Fe23+ ions trapped in an electron beam ion trap.
• Validated a novel technique for precision spectroscopy in the soft x-ray region.

Conclusions:

• The developed technique enables unprecedented accuracy in studying highly charged ions.
• This advancement is critical for future high-precision spectroscopic studies at upcoming x-ray free-electron lasers.
• The findings have the potential to yield fundamental insights into quantum electrodynamics.