Bond Dipole-Based Geometric Theory of Band Alignment
Prof. Shengbai Zhang
Rensselaer Polytechnic Institute, USA
Biography：
NAME: Zhang, Shengbai
POSITION TITLE: Professor.Emeritus
INSTITUTION: Rensselaer Polytechnic Institute
APPOINTMENTS:
2008-2025 Professor, Rensselaer Polytechnic Institute, Troy, NY
2008-2025 Senior Kodosky Constellation Chair, Rensselaer Polytechnic Institute, Troy, NY
2000-2007 Senior Scientist Il, National Renewable Energy Laboratory, Golden, CO
1997-2000 Senior Scientist I, National Renewable Energy Laboratory, Golden, CO
1994-1997 Staff Scientist, National Renewable Energy Laboratory, Golden, CO
1991-1994 Research Associate, National Renewable Energy Laboratory, Golden, CO
Abstract:
Study of band alignment is plagued by the lack of a common reference for periodic systems. Typicallyaverage potential is used as the reference. One may truncate a bulk to expose the vacuum level. However, with respectto such a level, the average potential is strongly orientation dependent. This happens because the average potential is aprojection of a nonintuitive bulk quadrupole tensor in the given direction. By introducing Wigner-Seitz atoms (WSA).which are charge neutral, maintain local crystal symmetry, and tessellate space, one can however reduce the tensor tothe expected scalar quantity, whereby setting the stage for a universal intrinsic band alignment.
Reference:
D.-H. Choe, D. West, S. Zhang, Phys. Rev. Lett. 121, 196802 (2018).
L. Kleinman, Phys. Rev. B 24, 7412 (1981).
D.-H. Choe, D. West, S. Zhang, Phys. Rev. B 103, 235202 (2021).
Z. Jiang, D. West, and S. Zhang, Featured Article, Appl. Phys. Rev. 12, 011411 (2025).
报告时间：2025年11月20日 9:00
报告地点：能源基础楼201会议室