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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Polarization effects in attosecond photoelectron spectroscopy
Jan Conrad Baggesen1, Lars Bojer Madsen
1Lundbeck Foundation Theoretical Center for Quantum System Research, Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark.
Physical Review Letters
|April 7, 2010
Summary
Polarization effects in attosecond and femtosecond streaking alter electron spectra. Accounting for these polarization-induced shifts is crucial for accurate analysis of ultrafast electron dynamics.
Area of Science:
- Attosecond science
- Quantum dynamics
- Molecular spectroscopy
Background:
- Ultrafast electron spectroscopy, like streaking, probes electron dynamics.
- Polarization of light pulses is a key experimental parameter.
- Understanding polarization effects is vital for accurate interpretation of spectral data.
Purpose of the Study:
- Investigate the influence of polarization effects on electron streaking spectra.
- Analyze how polarization modifies the conventional streaking spectrum.
- Determine the impact of polarization on temporal measurements in ultrafast spectroscopy.
Main Methods:
- Theoretical analysis of combined atto- and femtosecond pulses.
- Simulations of streaking spectra considering polarization.
- Angle-resolved photoelectron spectroscopy on oriented polar molecules.
- Study of atomic hydrogen 2p and 1s states.
Main Results:
- Polarization-induced terms alter the streaking spectrum.
- A field-following contribution modifies the conventional vector potential mapping.
- Apparent temporal shifts are introduced by polarization effects.
- A temporal shift of 50 attoseconds is predicted for atomic hydrogen.
Conclusions:
- Polarization effects significantly influence attosecond streaking measurements.
- Accurate analysis requires accounting for polarization-induced spectral modifications.
- Angle-resolved spectroscopy offers a method to isolate and study these effects.
- Understanding polarization is essential for precise temporal characterization of electron dynamics.
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