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arXiv · 1803.03977

Orbital Fingerprint of Topological Fermi Arcs in a Weyl Semimetal

Chul-Hee Min·Hendrik Bentmann·Jennifer N. Neu·Philipp Eck·Simon K. Moser·Tim Figgemeier·Maximilian Ünzelmann·Katharina Treiber·Peter Lutz·Roland Koch·Chris Jozwiak·Aaron Bostwick·Eli Rotenberg·Ronny Thomale·Giorgio Sangiovanni·Theo Siegrist·Domenico Di Sante·Friedrich Reinert
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Abstract

The monopnictides TaAs and TaP are well-established Weyl semimetals. Yet, a precise assignment of Fermi arcs, accomodating the predicted chiral charge of the bulk Weyl points, has been difficult in these systems, and the topological character of different surface features in the Fermi surface is not fully understood. Here, employing a joint analysis from linear dichroism in angle-resolved photoemission and first-principles calculations, we unveil the orbital texture on the full Fermi surface of TaP(001). We observe pronounced switches in the orbital texture at the projectedWeyl nodes, and show how they facilitate a topological classification of the surface band structure. Our findings establish a critical role of the orbital degrees of freedom in mediating the surface-bulk connectivity in Weyl semimetals.

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Chul-Hee Min, Hendrik Bentmann, Jennifer N. Neu, Philipp Eck, Simon K. Moser, Tim Figgemeier, Maximilian Ünzelmann, Katharina Treiber, Peter Lutz, Roland Koch, Chris Jozwiak, Aaron Bostwick, Eli Rotenberg, Ronny Thomale, Giorgio Sangiovanni, Theo Siegrist, Domenico Di Sante, Friedrich Reinert. 2018-03-11. Orbital Fingerprint of Topological Fermi Arcs in a Weyl Semimetal. https://doi.org/10.1103/physrevlett.122.116402

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