Extended Data Fig. 2: The participation ratio of the vibrational modes of the 2DPL model.
a, The participation ratio of each vibrational mode in the full frequency range. Most of the vibrational modes are phononic at low frequencies with a PR ≈ 2/3, distributed discretely. PR decays to a plateau over a wide frequency range with increasing frequency. Phonons transform to diffusons gradually, and the quasi-localised modes emerge simultaneously. This suggests phonon scattering by quasi-localised modes. At high frequencies above ωDebye (the Mobility edge), all the modes become strongly localised, which may be referred to as ‘Anderson localization’. b, The participation ratio of the longitudinal vibrational modes. The longitudinal phononic modes last up to much higher frequencies than the transverse ones.
