Abstract
The three-dimensional (3D) local atomic structures and crystal defects at the interfaces of heterostructures control their electronic, magnetic, optical, catalytic, and topological quantum properties but have thus far eluded any direct experimental determination. Here, we use atomic electron tomography to determine the 3D local atomic positions at the interface of a MoS2-WSe2 heterojunction with picometer precision and correlate 3D atomic defects with localized vibrational properties at the epitaxial interface. We observe point defects, bond distortion, and atomic-scale ripples and measure the full 3D strain tensor at the heterointerface. By using the experimental 3D atomic coordinates as direct input to first-principles calculations, we reveal new phonon modes localized at the interface, which are corroborated by spatially resolved electron energy-loss spectroscopy. We expect that this work will pave the way for correlating structure-property relationships of a wide range of heterostructure interfaces at the single-atom level.
Polina Anikeeva
Matoula S. Salapatas Professor and Head, Department of Materials Science and EngineeringProfessor, Brain and Cognitive SciencesDirector, K. Lisa Yang Brain-Body CenterAssociate Investigator, McGovern Institute for Brain ResearchAssociate Director, Research Laboratory of Electronics
My goal is to combine the current knowledge of biology and nanoelectronics to develop materials and devices for minimally invasive treatments for neurological and neuromuscular diseases.