Phonon lifetimes from first-principles self-consistent lattice dynamics.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Computational Materials Science

Background:

• First-principles phonon lifetime calculations are crucial for understanding material properties.
• Traditional methods like molecular dynamics and density functional perturbation theory have limitations, including computational cost and assumptions of zero-temperature dynamic stability.

Purpose of the Study:

• To present a novel and efficient first-principles method for calculating phonon lifetimes.
• To develop a method not restricted to dynamically stable crystal phases at 0 K.
• To offer a more computationally effective alternative to existing methods, particularly molecular dynamics.

Main Methods:

• The study employs a new method based on the self-consistent ab initio lattice dynamical approach.
• This method allows for calculations beyond the 0 K dynamically stable crystal structure assumption.

Main Results:

• The new method was successfully tested by calculating phonon lifetimes for the body-centered cubic (bcc) phase of Li, Na, Ti, and Zr.
• The presented approach demonstrates effectiveness and improved efficiency compared to standard molecular dynamics calculations.

Conclusions:

• The developed method provides a robust and efficient way to compute phonon lifetimes from first principles.
• It expands the applicability of theoretical calculations to materials and phases not stable at 0 K, offering valuable insights into their dynamic behavior.