Selective Nonthermal Melting in Phlogopite under Ultrafast Energy Deposition

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Materials Science

Background:

• Phlogopite mica (KMg3(AlSi3O10)-(OH)2) is a complex magnesium-rich mineral.
• Understanding its response to high-energy excitation is crucial for materials science applications.

Purpose of the Study:

• To investigate the ultrafast electronic and atomic responses of phlogopite mica to excitation.
• To predict phase transitions and structural changes under varying energy doses.

Main Methods:

• Utilized a hybrid model combining tight-binding molecular dynamics with transport Monte Carlo and the Boltzmann equation.
• Simulated the effects of deposited energy doses on the phlogopite atomic and electronic systems.

Main Results:

• Predicted transient superionic states with hydrogen migration at ~0.17 eV/atom.
• Observed Mg atom diffusion and a superionic-superionic phase transition at ~0.4 eV/atom.
• Demonstrated atomic lattice destabilization and bandgap collapse leading to a metallic state at higher doses (~0.5-0.9 eV/atom).
• Identified nonthermal acceleration of K and O atoms at very high energy doses.

Conclusions:

• Phlogopite mica exhibits complex phase transitions under ultrafast excitation, transitioning from superionic states to a metallic conductor.
• The study provides insights into the dynamic behavior of minerals under extreme conditions, relevant for materials science and geophysics.