The method of ab initio molecular dynamics, based on finite-temperature density-functional theory, is used to simulate laser heating of crystalline silicon. We found that a high concentration of excited electrons dramatically weakens the covalent bonding. As a result the system undergoes a melting transition to a metallic state. We studied several structural, dynamical, electronic, and bonding properties of this phase of silicon. In contrast to ordinary liquid silicon, this liquid is characterized by a high coordination number and a strong reduction of covalent-bonding effects. However this phase is transient. In fact, by strongly reducing the level of electronic excitation, liquid silicon reverts very rapidly to its usual properties.

Additional Metadata
Journal Phys. Rev. B
Citation
Silvestrelli, P. L, Alavi, A, Parrinello, M, & Frenkel, D. (1997). Structural, dynamical, electronic, and bonding properties of laser-heated silicon: An ab initio molecular-dynamics study. Phys. Rev. B, 56, 3806–3812.