Surface properties of 3D Weyl semimetal BaMnSb<sub>2</sub>
ORAL
Abstract
Recently BaMnSb2 was found to be a 3D Weyl semimetal with 2D electronic structure where the Dirac cone was predicted from 1st principles electronic structure calculations to result from the Sb in the square lattice. One of fingerprints of Weyl fermions is the formation of Fermi Arc at the Fermi level, which can be measured by techniques such as ARPES and scanning tunneling microscopy (STM). However, these techniques require an in-depth understanding of the surface properties. Freshly cleaved BaMnSb2 surface was studied using STM and Low energy electron diffraction (LEED). We found two cleavage terminations that are all at Ba layers, but one is above the Sb/Mn layer and the other is above the Sb square lattice. We found although both surfaces show similar 2x1 surface structure reconstructions, their electronic properties are drastically different. Both surfaces are semiconducting with no sign of the Dirac-type cones. The existence of defects can greatly modify the local density of state to create electronic phase separations on the surface. The defects behavior will be discussed based on surface characterization, theoretical calculations and global transport properties.
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Presenters
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Rongying Jin
- Department of Physics and Astronomy, Louisiana State University
- Physics and Astronomy, Louisiana State Univ - Baton Rouge
- Department of Physcis and Astronomy, Louisiana State University
- Department of Physics & astronomy, Louisiana state University
- Department of Physics, Louisiana State University
- Louisiana State Univ - Baton Rouge
- Physics and Astronomy, Louisiana State University
- Physics, Louisiana State Univ
- Department of Physics and Astronomy,, Louisiana State Univ - Baton Rouge