Advanced Institute for Material Research (AIMR), Tohoku University
Quantum Materials at the atomic scale: Visualization and Designing
One of the most critical challenges at the frontier of materials physics is the ability to control band structure, both realizing novel phenomena and for practical functionalities. In this talk, I will describe our atomic scale investigations of novel quantum materials called topological crystalline insulators (TCIs) [1-5]. In TCIs, topology and crystal symmetry intertwine to create massless Dirac electrons, which can be described by the same equations used for relativistic particles travelling close to the speed of light. Using Landau level spectroscopy and atomic resolution imaging in TCIs, we have discovered massive Dirac electrons coexisting with massless Dirac elctrons [2,5]. Our findings experimentally demonstrate the unique and extraordinary tunability of Dirac electrons in TCIs, which provides a significant step for realizing fundamentally and practically important quantum states vis strain engineering. As the final part of this talk, I will also introduce my recent attempt of combing visualization technique with thin film based material design.
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