Amorphous Solid Vibrational Modes
Soft modes, boson peak, and participation ratio in disordered solids
Parameters
N atoms:
60
Disorder δ:
0.40
Range cutoff r_c:
2.0
Mode index:
3
Regenerate
Animate Mode
Boson peak ω_BP
—
Soft modes (<0.5)
—
Participation ratio
—
Boson peak:
excess low-frequency modes in glasses above Debye (ω²) baseline. DOS/ω² shows a peak.
Soft modes:
near-zero frequency — quasi-localized, rearrangement precursors.
Participation ratio:
PR=1 (delocalized), PR~1/N (localized).