A First-Principles Time-Dependent Density Functional Theory Framework for Spin and Time-Resolved Angular-Resolved...

Area of Science:

• Computational Physics
• Materials Science
• Quantum Chemistry

Background:

• Angle-resolved photoelectron spectroscopy (ARPES) is crucial for understanding electronic structures.
• Simulating ARPES, especially with time-dependent phenomena, presents significant theoretical challenges.
• Existing methods often lack the flexibility to handle arbitrary laser fields and complex nanostructures.

Purpose of the Study:

• To introduce a novel first-principles theoretical approach for simulating spin, time, and angular-resolved photoelectron spectroscopy (ARPES).
• To develop a method applicable to a wide range of materials including surfaces, thin films, and low-dimensional nanostructures.
• To enable simulations of complex electron dynamics under arbitrary laser irradiation, including pump-probe scenarios.

Main Methods:

• Utilizing time-dependent density functional theory (TDDFT) to model the real-time evolution of electrons.
• Extending the t-SURFF method to periodic systems, named t-SURFFP.
• Calculating photoelectron spectra by analyzing the ionization current flux through a surface.

Main Results:

• The t-SURFFP method successfully simulates ARPES from first-principles for various materials.
• Demonstrated applicability to graphene, monolayer and bilayer WSe2, and hexagonal boron nitride (hBN).
• The method handles diverse laser configurations and ionization dynamics without restrictive assumptions.

Conclusions:

• The t-SURFFP method offers a versatile and accurate tool for simulating ARPES.
• This approach significantly enhances the capability to study electronic properties of advanced materials.
• Enables detailed investigations of light-matter interactions in low-dimensional systems.