Compact realization of all-attosecond pump-probe spectroscopy

Area of Science:

• Ultrafast Science
• Attosecond Spectroscopy
• Quantum Dynamics

Background:

• Attosecond-pump attosecond-probe spectroscopy (APAPS) is crucial for studying ultrafast phenomena.
• Previous APAPS setups suffered from low repetition rates and large footprints, limiting accessibility.
• Widespread adoption of APAPS has been hindered by technical limitations.

Purpose of the Study:

• To develop a more accessible and practical APAPS system.
• To enable high-repetition-rate, two-color attosecond spectroscopy.
• To facilitate investigations of fundamental processes on attosecond timescales.

Main Methods:

• Utilized a commercial laser system operating at 1 kHz repetition rate.
• Implemented straightforward post-compression in a hollow-core fiber.
• Employed a compact high-harmonic generation (HHG) setup with an out-of-focus geometry.
• Exploited transient blueshift in the HHG medium for intense extreme-ultraviolet (XUV) pulse generation.

Main Results:

• Demonstrated two-color APAPS at a 1 kHz repetition rate.
• Generated near-isolated attosecond pulses.
• Successfully performed one-color and two-color XUV-pump XUV-probe experiments.
• Achieved a compact and efficient APAPS setup.

Conclusions:

• The developed APAPS system significantly enhances accessibility for ultrafast science research.
• This technique allows selective pumping and probing on extremely short timescales.
• Enables investigations into fundamental processes previously inaccessible with other methods.