Presence of Exotic Electronic Surface States in LaBi and LaSb

Abstract

Extremely high magnetoresistance (XMR) in the lanthanum monopnictides La$X$ ($X$ = Sb, Bi) has recently attracted interest in these compounds as candidate topological materials. However, their perfect electron-hole compensation provides an alternative explanation, so the possible role of topological surface states requires verification through direct observation. Our angle-resolved photoemission spectroscopy (ARPES) data reveal multiple Dirac-like surface states near the Fermi level in both materials. Intriguingly, we have observed circular dichroism in both surface and near-surface bulk bands. Thus the spin-orbit coupling-induced orbital and spin angular momentum textures may provide a mechanism to forbid backscattering in zero field, suggesting that surface and near-surface bulk bands may contribute strongly to XMR in La$X$. The extremely simple rock salt structure of these materials and the ease with which high-quality crystals can be prepared suggests that they may be an ideal platform for further investigation of topological matter.

References in corpus (7)

• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Topological Insulators with Inversion Symmetry
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• A topological Dirac insulator in a quantum spin Hall phase : Experimental observation of first strong topological insulator
• Weyl semimetal phase in non-centrosymmetric transition metal monophosphides
• Surface States of the Topological Insulator Bi_{1-x}Sb_x
• Circular dichroism in angle-resolved photoemission spectroscopy of topological insulators

Cited by in corpus (27)

• Evidence of topological insulator state in the semimetal LaBi
• Three-dimensional band structure of LaSb and CeSb:Absence of band inversion
• Origin of the Extremely Large Magnetoresistance in the Semimetal YSb
• Large magnetoresistance in type-II Weyl semimetal WP${}_2$
• Separation of Electron and Hole Dynamics in the Semimetal LaSb
• Extremely large magnetoresistance and Fermi surface topology of PrSb
• Pressure-induced topological phase transition in LaSb: First-principles study
• Observation of Open-Orbit Fermi Surface Topology in Extremely Large Magnetoresistance Semimetal MoAs${}_2$
• Fermi surface topology and large magnetoresistance in the topological semimetal candidate PrBi
• Unusual change in the Dirac-cone energy band upon two-step magnetic transition in CeBi
• Observation of gapped state in rare-earth monopnictide HoSb
• Complex electronic structure evolution of NdSb across the magnetic transition
• Directional effects of antiferromagnetic ordering on the electronic structure in NdSb
• Probing the Origin of Extreme Magnetoresistance in Pr/Sm Mono-Antimonides/Bismuthides
• Behavior of gapped and ungapped Dirac cones in an antiferromagnetic topological metal, SmBi
• Antiferromagnetic topological insulator with selectively gapped Dirac cones
• LaN Structural and Topological Transitions Driven by Temperature and Pressure
• Dirac nodal lines in the quasi-one-dimensional ternary telluride TaPtTe${}_5$
• Large Magnetoresistance and Nontrivial Berry Phase in Nb3Sb Crystals with A15 Structure
• Temperature-dependent Fermi surface probed by Shubnikov-de Haas oscillations in topological semimetal candidates DyBi and HoBi
• Unexpected changes in the band structure within AFM1 state of CeBi
• Structural, electronic and topological properties of 3D TmBi compound
• First-principles study on the electron-phonon coupling and magnetoresistance of LaBi under pressure
• Direct evidence of electron-hole compensation for XMR in topologically trivial YBi
• Long-range magnetic order induced surface state in GdBi and DyBi
• Unconventional band splitting of CeSb in the devil's staircase transition
• Spin-orbital order and excitons in magnetoresistive HoBi