A high-order harmonic generation apparatus for time- and angle-resolved photoelectron spectroscopy

Area of Science:

• Condensed matter physics
• Ultrafast spectroscopy

Background:

• Correlated materials exhibit complex electronic behaviors under non-equilibrium conditions.
• Understanding band structure dynamics is key to controlling material properties.
• Sub-picosecond time resolution is essential to capture ultrafast electron-phonon interactions.

Purpose of the Study:

• To present a novel tabletop apparatus for time- and angle-resolved photoelectron spectroscopy.
• To investigate the dynamics of band structures in correlated materials driven far from equilibrium.
• To achieve sub-picosecond time resolution for studying electron-phonon equilibration.

Main Methods:

• Utilizing femtosecond laser pulses to excite correlated materials.
• Employing laser-driven high-order harmonic generation for probing.
• Implementing a grating monochromator for tunable photon energies (up to 40 eV).
• Achieving a photon energy bandwidth of 150 meV and 100 fs pulse duration.

Main Results:

• The setup enables detailed investigation of band structure dynamics.
• It allows for mapping of valence bands at different kz and detection of outer core states.
• The achieved time resolution is sufficient to observe electron-phonon equilibration dynamics.

Conclusions:

• The developed tabletop setup is a powerful tool for studying non-equilibrium states in materials.
• This technique provides unprecedented insight into ultrafast electronic processes.
• It opens new avenues for exploring quantum phenomena in correlated systems.