title: Creases on the interface between two soft materials.
abstract: Theory and experiment are presented to show that an interface between two soft materials under compression can form creases, a type of bifurcation distinct from wrinkles. While creases bifurcate from a state of flat interface by a deformation localized in space and large in amplitude, wrinkles bifurcate from a state of flat interface by a deformation nonlocal in space and infinitesimal in amplitude. The interfacial creases set in at a lower critical compression than interfacial wrinkles, but higher than surface creases. The condition for the onset of interfacial creases is scale-free, and is calculated in terms of elastic moduli, pre-strains and applied strains.
authors.affiliation: School of Engineering and Applied Sciences, Kavli Institute for Nanobio Science and Technology, Harvard University, Cambridge, Massachusetts 02138, USA. suo@seas.harvard.edu.
authors.forename: Lihua
authors.initials: L
authors.lastname: Jin
authors.forename: Dayong
authors.initials: D
authors.lastname: Chen
authors.forename: Ryan C
authors.initials: RC
authors.lastname: Hayward
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Suo