Atomic transient recorder.

Area of Science:

• Atomic Physics
• Quantum Mechanics
• Ultrafast Science

Background:

• The electron's orbital motion in the hydrogen atom defines the attosecond (as = 10^-18 s) timescale for atomic dynamics.
• Real-time recording of atomic transients necessitates excitation and probing on this attosecond scale.
• Advances in generating sub-femtosecond (fs = 10^-15 s) extreme ultraviolet (XUV) pulses enable exploration of the attosecond regime.

Purpose of the Study:

• To demonstrate the generation and measurement of single 250-attosecond XUV pulses.
• To utilize these pulses for exciting atoms and probing the dynamics of ejected electrons.
• To develop a transient recorder capable of resolving atomic electron dynamics within the Bohr orbit time.

Main Methods:

• Generation and measurement of single 250-attosecond XUV pulses.
• Excitation of atoms using these attosecond XUV pulses.
• Employing intense, waveform-controlled, few-cycle laser pulses to obtain tomographic images of electron time-momentum distributions.

Main Results:

• Successful generation and measurement of single 250-attosecond XUV pulses.
• Tomographic imaging of primary photoelectrons provided accurate information on the excitation pulse's duration and frequency sweep.
• Tomographic imaging of secondary Auger electrons offered insights into electronic shell relaxation dynamics.

Conclusions:

• The developed transient recorder, using ~750-nm laser probes and ~100-eV excitation, can resolve atomic electron dynamics on the attosecond timescale.
• This technique opens new avenues for studying ultrafast electron dynamics in atoms.
• The ability to probe electron motion in real-time advances our understanding of fundamental atomic processes.