Language
English
Publication Date
3-25-2025
Journal
Proceedings of the National Academy of Sciences of the United States of America
DOI
10.1073/pnas.2425200122
PMID
40106353
PMCID
PMC11962411
PubMedCentral® Posted Date
3-19-2025
PubMedCentral® Full Text Version
Post-print
Abstract
Thermally induced ripples are intrinsic features of nanometer-thick films, atomically thin materials, and cell membranes, significantly affecting their elastic properties. Despite decades of theoretical studies on the mechanics of suspended thermalized sheets, controversy still exists over the impact of these ripples, with conflicting predictions about whether elasticity is scale-dependent or scale-independent. Experimental progress has been hindered so far by the inability to have a platform capable of fully isolating and characterizing the effects of ripples. This knowledge gap limits the fundamental understanding of thin materials and their practical applications. Here, we show that thermal-like static ripples shape thin films into a class of metamaterials with scale-dependent, customizable elasticity. Utilizing a scalable semiconductor manufacturing process, we engineered nanometer-thick films with precisely controlled frozen random ripples, resembling snapshots of thermally fluctuating membranes. Resonant frequency measurements of rippled cantilevers reveal that random ripples effectively renormalize and enhance the average bending rigidity and sample-to-sample variations in a scale-dependent manner, consistent with recent theoretical estimations. The predictive power of the theoretical model, combined with the scalability of the fabrication process, was further exploited to create kirigami architectures with tailored bending rigidity and mechanical metamaterials with delayed buckling instability.
Published Open-Access
yes
Recommended Citation
Zhou, Jian; Huang, Richard; Moldovan, Nicolaie; et al., "Rippled Metamaterials With Scale-Dependent Tailorable Elasticity" (2025). Faculty, Staff and Students Publications. 8192.
https://digitalcommons.library.tmc.edu/baylor_docs/8192