The scaling of the vibrational density of states in quasi-2D nanoconfined solids

Yu, Y.*; Yang, C.*; Baggioli, M.*; Phillips, A. E.*; Zaccone, A.*; Zhang, L.*; 梶本 亮一  ; 中村 充孝   ; Yu, D.*; Hong, L.*

Yu, Y.*; Yang, C.*; Baggioli, M.*; Phillips, A. E.*; Zaccone, A.*; Zhang, L.*; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Yu, D.*; Hong, L.*

The vibrational properties of crystalline bulk materials are well described by Debye theory, which successfully predicts the quadratic low-frequency scaling of the vibrational density of states. However, the analogous framework for nanoconfined materials with fewer degrees of freedom has been far less well explored. Using inelastic neutron scattering, we characterize the vibrational density of states of amorphous ice confined inside graphene oxide membranes and we observe a crossover from the Debye scaling to an anomalous behaviour upon reducing the confinement size L.