Yafei Zhang received his Ph.D. in Solid Mechanics at Tsinghua University, Beijing, China, under the supervision of Prof. Changqing Chen and Prof. Quanshui Zheng. He is currently working as a research assistant in the Department of Engineering Mechanics, Tsinghua University.

 

Yafei’s dissertation focused mainly on controllable deformation localization and structural phase transitions in mechanical metamaterials. This work aims to establish physical frameworks, i.e., static soliton-lattices, strain domain walls, and topological defects, to program ordered/desired deformation localization into metamaterials. Yafei introduced the phi^4 model, the Klein-Gordon equation, and Landau theory to describe the controllable phase transition behaviors under mechanical loadings. Novel phenomenon/mechanism, intriguing concepts/functionalities, and general theoretical frameworks/strategies are displayed in his research. It refreshes the traditional perception that localized deformations are sensitive to defects, rendering the location and dimension of localization zones hard to predict.

 

During his time as a research assistant, Yafei has shifted his interest slightly to nonlinear topological mechanics. He is focusing on the evaluation of nonlinear edge modes, geometric frustration, and boundary effects in topological mechanical lattices. He is also attempting to explore the connections between static deformation of metamaterials and non-hermitian physics.

 

In the spring of 2022, Yafei will be working with Prof. Eran Sharon, Prof. Michael Moshe, and their research groups as a Postdoctoral Fellow in the Racah Institute of Physics at The Hebrew University of Jerusalem. He plans to investigate the nonlinear mechanics and geometry of aperiodic, self-morphing metamaterials, using a combination of experimental, theoretical and numerical tools.