Extended Data Fig. 9: Vibrational properties of the 2DKA Model.

a, VDOS of the low-temperature glass. b, The corresponding VDOS with a fit to the log-normal function (red dashed line), from which we estimate the boson peak frequency as ~ 1.3. c, Two dimensional contour of the transverse dynamical structure factors. The orange shade indicates the boson peak frequency range. d, Dispersion relation in a wide frequency-wavenumber range, with the existence of quasi-localised modes around the boson peak frequency. e, Enlarged dispersion relation for transverse phonons, from which we estimate the transverse Ioffe-Regel limit as 1.6, close to ω_BP.