Characterizing strong-field tunneling ionization with a phase-dependent THz polarization spectrum

Area of Science:

• Atomic and Molecular Physics
• Quantum Optics
• Ultrafast Science

Background:

• Terahertz (THz) radiation is crucial for understanding electron dynamics in strong-field ionization.
• Asymmetric ionization of wavepackets generates detectable THz emission.
• Characterizing electron behavior requires precise measurement of ionization processes.

Purpose of the Study:

• To propose and validate a phase-dependent terahertz polarization (PTP) spectrum for characterizing and controlling tunneling ionization.
• To establish the PTP spectrum as a tool for probing electron dynamics and structural properties.
• To demonstrate all-optical characterization of ultrafast atomic and molecular ionization.

Main Methods:

• Utilizing a phase-dependent terahertz polarization (PTP) spectrum.
• Employing the classical trajectory Monte Carlo (CTMC) method.
• Applying an analytical model based on the virial theorem.
• Benchmarking with the rigorous solution of the time-dependent Schrödinger equation (TDSE).

Main Results:

• The PTP spectrum precisely measures Coulomb effects influenced by the two-color laser's relative phase.
• Electron manipulation is achievable by controlling relative phase and laser intensity.
• The PTP spectrum calibrates relative phase and reconstructs tunneling positions accurately.
• The analytical model provides robust, high-precision reconstruction of time-averaged tunneling positions.

Conclusions:

• The PTP spectrum is a novel, high-precision tool for all-optical characterization of ultrafast atomic and molecular ionization.
• This method enables detailed insights into electron dynamics and structural properties.
• Controlling laser parameters via the PTP spectrum allows for manipulation of electron behavior.