Kavli Affiliate: Alessandra Lanzara
| First 5 Authors: Ivan Pelayo, Derek Bergner, Archibald J. Williams, Jiayuwen Qi, Mahfuzun Nabi
| Summary:
PtTe$_2$ and PdTe$_2$ are among the first transition metal dichalcogenides
that were predicted to host type-II Dirac fermions, exotic particles prohibited
in free space. These materials are layered and air-stable, which makes them top
candidates for technological applications that take advantage of their
anisotropic magnetotransport properties. Here, we provide a detailed
characterization of the electronic structure of PtTe$_2$ and PdTe$_2$ using
Angle Resolved Photoemission Spectroscopy ARPES and Density Functional Theory
DFT calculations, unveiling a new three-dimensional Dirac-like dispersion in
these materials. Through the use of circularly polarized light, we report a
different behavior of such dispersion in PdTe$_2$ compared to PtTe$_2$, that we
relate to our DFT calculations. Additionally, our circular dichroism data shows
a sharp difference between the known type-II Dirac cones and the topologically
protected surface states in these materials. Finally, we present an analysis
that links our experimental and theoretical data to the different symmetries
associated to the crystallographic space group shared by PtTe$_2$ and PdTe$_2$.
Our work provides a useful reference for the ARPES characterization of other
transition metal dichalcogenides with topological properties and illustrates
the use of circular dichroism as an additional tool to differentiate the
topological character of two otherwise equivalent band dispersions and to
identify new dispersions.
| Search Query: ArXiv Query: search_query=au:”Alessandra Lanzara”&id_list=&start=0&max_results=3