Topological Lifshitz transition in Weyl semimetal NbP decorated with heavy elements

Abstract

Studies of the Fermi surface modification after in-situ covering NbP semimetal with heavy elements Pb and Nb ultrathin layers were performed by means of angle-resolved photoemission spectroscopy (ARPES). First, the electronic structure was investigated for pristine single crystals with two possible terminations (P and Nb) of the (0 0 1) surface. The nature of the electronic states of these two cleaving planes is different: P-terminated surface shows spoon and bow tie shaped fingerprints, whereas these shapes are not present in Nb-terminated surfaces. ARPES studies show that even 1 monolayer (ML) of Pb causes topological quantum Lifshitz transition (TQLT) in P- and Nb-terminated surfaces. Deposited Pb 5d electrons have wide extended atomic orbitals which leads to strong hybridization with Pb-terminated surface and a corresponding shift in the Fermi energy. Nb has less capability to perturb the system than Pb because Nb has weaker spin-orbit coupling than Pb. Nb-terminated surface subjected to surface decoration with approximately 1.3 ML of Nb shows no dramatic modification in the Fermi surface. In the case of Nb decorated P-terminated surface, deposition of approximately 1 ML modifies the electronic structure of NbP and it is on the verge of TQLT. Despite the strong spin-orbit and strong hybridization of the heavy elements on the surface, it is possible to observe the TQLT of the surface states thanks to the robustness of the bulk topology.

arXiv comment9 Pages, 8 Figures

References in corpus (19)

• Type-II Weyl Semimetals
• Topological Materials: Weyl Semimetals
• Experimental discovery of Weyl semimetal TaAs
• Extremely large magnetoresistance and ultrahigh mobility in the topological Weyl semimetal NbP
• Superconductivity in Weyl Semimetal Candidate MoTe2
• Discovery of Weyl fermion semimetals and topological Fermi arc states
• Structured Weyl Points in Spin-Orbit Coupled Fermionic Superfluids
• Topological surface states and Fermi arcs of the noncentrosymmetric Weyl semimetals TaAs, TaP, NbAs, and NbP
• Fermi arc topology and interconnectivity in Weyl fermion semimetals TaAs, TaP, NbAs, and NbP
• Topological Lifshitz transitions
• Direct Observation of Nonequivalent Fermi-Arc States of Opposite Surfaces in Noncentrosymmetric Weyl Semimetal NbP
• Three-Dimensional Electronic Structure of type-II Weyl Semimetal WTe${}_2$
• Topological Lifshitz Transitions and Fermi Arc Manipulation in Weyl Semimetal NbAs
• Quasiparticle interference on type-I and type-II Weyl semimetal surfaces: a review
• Hidden Weyl Points in Centrosymmetric Paramagnetic Metals
• Electronic properties of TaAs2 topological semimetal investigated by transport and ARPES
• Topological states in superlattices of HgTe-class materials for engineering three-dimensional flat bands
• Conductance spectra of (Nb, Pb, In)/NbP -- superconductor/Weyl semimetal junctions
• Conductance oscillations and zero-bias anomaly in a single superconducting junction to a three-dimensional $B{i}_{2}T{e}_3$ topological insulator