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Carrier-Envelope Phase-Dependent Strong-Field Excitation
D Chetty1, R D Glover1,2, X M Tong3
1Centre for Quantum Dynamics, Griffith University, Brisbane, Queensland 4111, Australia.
Physical Review Letters
|May 16, 2022
Summary
The carrier-envelope phase (CEP) of laser pulses critically influences atomic excitation. Tailored laser fields can control this strong-field process, with distinct behaviors observed in multiphoton and tunneling regimes.
Area of Science:
- Atomic and Molecular Physics
- Quantum Optics
- Strong-Field Physics
Background:
- The carrier-envelope phase (CEP) of ultrashort laser pulses is crucial for controlling light-matter interactions.
- Understanding atomic excitation in intense laser fields requires exploring the transition between multiphoton and tunneling ionization regimes.
Purpose of the Study:
- To investigate the influence of the CEP of few-cycle laser pulses on the atomic excitation process.
- To examine the excitation rates of argon atoms at laser intensities straddling the multiphoton and tunneling regimes.
Main Methods:
- Joint experimental and theoretical study.
- Numerical simulations to model bound-state population dynamics.
- Experimental measurements of atomic excitation rates.
Main Results:
- The bound-state population in argon is highly sensitive to both laser intensity and CEP.
- Experimental data show excellent agreement with theoretical predictions.
- A clear transition in CEP-dependent behavior is observed between the multiphoton and tunneling ionization regimes.
Conclusions:
- Precisely tailored laser fields can achieve coherent control over strong-field atomic excitation.
- The study highlights distinct CEP effects in different ionization regimes, crucial for advanced laser control applications.
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