Year: 2018
Type: article
Abstract: Among the quantum materials that have recently gained interest are the topological insulators, wherein symmetry-protected surface states cross in reciprocal space, and the Dirac nodal-line semimetals, where bulk bands touch along a line in k-space. However, the existence of multiple fermion phases in a single material has not been verified yet. Using angle-resolved photoemission spectroscopy (ARPES) and first-principles electronic structure calculations, we systematically study the metallic material Hf2Te2P and discover properties, which are unique in a single topological quantum material. We experimentally observe weak topological insulator surface states and our calculations suggest additional strong topological insulator surface states. Our first-principles calculations reveal a one-dimensional Dirac crossing—the surface Dirac-node arc—along a high-symmetry direction which is confirmed by our ARPES measurements. This novel state originates from the surface bands of a weak topological insulator and is therefore distinct from the well-known Fermi arcs in semimetals.
Source: Nature Communications
Authors: M. Mofazzel Hosen, Klauss Dimitri, Ashis K. Nandy, Alex Aperis, Raman Sankar, Gyanendra Dhakal, Pablo Maldonado, Firoza Kabir, Christopher Sims, Fangcheng Chou, Dariusz Kaczorowski, Tomasz Durakiewicz, Peter M. Oppeneer, Madhab Neupane
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $6,990
OpenAlex ID: W2963223099