Strain and defect engineering are effective means to achieve versatile functionalities in materials. Due to their weak interlayer coupling, several physical properties of van der Waals (vdW) solids show high sensitivity with strain, e.g. bandgap shift, Raman peak shift and thermal conductivity change. With mechanical stretching/bending approach, strains of several percent can be realized. Very recently, a diamond anvil cell technique was introduced to generate more than 10% hydrostatic compressive strain in vdW semiconductors, making it possible to study transport phenomena under extremely nonequilibrium conditions. Furthermore, nanoscale wrinkles/crumples, blisters and bubbles can be created to enable localized, heterogeneous straining of vdW semiconductors. Additionally, rich forms of defects are present in vdW solids synthesized with chemical vapor deposition and molecular beam epitaxy. Defects are usually pictured as carrier traps or recombination centers. Recent discoveries suggest that defects can also serve as quantum emitters or spin trappers, and enable new quantum phenomena such as hydrodynamic electron transport.
This symposium will cover a broad range of emergent functional phenomena in vdW solids enabled by strain and defect engineering, including thermal, electrical, magnetic properties, as well as some quantum phenomena involving many-body interactions among phonons, electrons, magnons, etc. The materials will include not only graphitic materials, transition metal dichalcogenides, but also some emerging families of ferromagnetic materials, such as FePS3.
Sun Yat-sen University
School of Physics
Los Alamos National Laboratory
Materials Physics & Applications, Center for Integrated Nanotechnologies
University of California, Irvine
Department of Mechanical and Aerospace Engineering
The University of Texas at Austin