Real-space, real-time approach to quantum-electrodynamical time-dependent density functional theory.

Area of Science:

• Quantum Chemistry
• Computational Physics
• Materials Science

Background:

• Accurate simulation of quantum systems is crucial for understanding molecular behavior.
• Modeling molecules within confined environments (cavities) presents unique challenges.
• Existing methods may struggle with the complex interactions between light and matter in such systems.

Purpose of the Study:

• To develop and validate a novel computational approach for quantum-electrodynamical time-dependent density functional theory.
• To accurately simulate the behavior of molecules placed inside optical cavities.
• To investigate key optical and electronic properties influenced by cavity environments.

Main Methods:

• Solving quantum-electrodynamical time-dependent density functional theory equations.
• Time-propagating the wave function on a combined Fock-space and real-space grid.
• Applying the method to model molecules within optical cavities.

Main Results:

• Demonstrated the accuracy of the developed approach for molecules in cavities.
• Analyzed the dependence of energies, wave functions, and optical absorption spectra on coupling strength and light frequency.
• Quantified Rabi splitting magnitudes and described high harmonic generation within cavities.

Conclusions:

• The new quantum-electrodynamical time-dependent density functional theory method provides a reliable tool for studying light-matter interactions in confined systems.
• The approach accurately captures complex phenomena like Rabi splitting and high harmonic generation.
• This work advances the simulation capabilities for molecular systems interacting with electromagnetic fields in cavities.