Observation and control of maximal Chern numbers in a chiral topological semimetal

Abstract

Topological semimetals feature protected nodal band degeneracies characterized by a topological invariant known as the Chern number (C). Nodal band crossings with linear dispersion are expected to have at most |C|=4, which sets an upper limit to the magnitude of many topological phenomena in these materials. Here we show that the chiral crystal PdGa displays multifold band crossings, which are connected by exactly four surface Fermi-arcs, thus proving that they carry the maximal Chern number magnitude of 4. By comparing two enantiomers, we observe a reversal of their Fermi-arc velocities, which demonstrates that the handedness of chiral crystals can be used to control the sign of their Chern numbers.

Accepted manuscript

References in corpus (22)

• Electronic Structure of Pyrochlore Iridates: From Topological Dirac Metal to Mott Insulator
• Weyl and Dirac Semimetals in Three Dimensional Solids
• Topological nodal semimetals
• Chiral Anomaly and Classical Negative Magnetoresistance of Weyl Metals
• Beyond Dirac and Weyl fermions: Unconventional quasiparticles in conventional crystals
• Recent developments in transport phenomena in Weyl semimetals
• Quantized circular photogalvanic effect in Weyl semimetals
• Multi-Weyl Topological Semimetals Stabilized by Point Group Symmetry
• Topological quantum properties of chiral crystals
• Multiple types of topological fermions in transition metal silicides
• Large Fermi Arcs in Unconventional Weyl Semimetal RhSi
• Discovery of topological chiral crystals with helicoid arc states
• New classes of chiral topological nodes with non-contractible surface Fermi arcs in CoSi
• Chiral anomaly and transport in Weyl metals
• Observation of Chiral Fermions with a Large Topological Charge and and Associated Fermi-Arc Surface States in CoSi
• Chiral Topological Semimetal with Multifold Band Crossings and Long Fermi arcs
• Chiral Optical Response of Multifold Fermions
• A facility for the analysis of the electronic structures of solids and their surfaces by synchrotron radiation photoelectron spectroscopy
• Composite Weyl nodes stabilized by screw symmetry with and without time reversal
• Difference frequency generation in topological semimetals
• Multifold nodal points in magnetic materials
• Observation of multiple types of topological fermions in PdBiSe

Cited by in corpus (65)

• Weyl, Dirac and high-fold chiral fermions in topological quantum materials
• All Topological Bands of All Nonmagnetic Stoichiometric Materials
• Topological quantum materials from the viewpoint of chemistry
• Topological Materials Discovery from Crystal Symmetry
• Topology and geometry under the nonlinear electromagnetic spotlight
• A Charge-Density-Wave Topological Semimetal
• Twofold quadruple Weyl nodes in chiral cubic crystals
• Symmetry-enforced topological nodal planes at the Fermi surface of a chiral magnet
• Quasi-symmetry protected topology in a semi-metal
• Momentum-space signatures of Berry flux monopoles in a Weyl semimetal
• Weyl phonons in chiral crystals
• Tunable Chirality-dependent Nonlinear Electrical Responses in 2D Tellurium
• Discovery of a maximally charged Weyl point
• Tunable Circular Photogalvanic and Photovoltaic Effect in 2D Tellurium with Different Chirality
• Intrinsic negative magnetoresistance from the chiral anomaly of multifold fermions
• Parallel spin-momentum locking in a chiral topological semimetal
• Kramers Weyl Semimetals as Quantum Solenoids and Their Applications in Spin-Orbit Torque Devices
• Network of topological nodal planes, multifold degeneracies, and Weyl points in CoSi
• Chirality locking charge density waves in a chiral crystal
• Fermi arc reconstruction in synthetic photonic lattice
• Dual Haldane sphere and quantized band geometry in chiral multifold fermions
• Phonon magnetochiral effect of band-geometric origin in Weyl semimetals
• Atomically Sharp Internal Interface in a Chiral Weyl Semimetal Nanowire
• Hierarchy of quasi-symmetries and degeneracies in chiral crystal materials CoSi
• Computing observables without eigenstates: applications to Bloch Hamiltonians
• Realization of Practical Eightfold Fermions and Fourfold van Hove Singularity in TaCo${}_2$Te${}_2$
• Anisotropic phonon-mediated electronic transport in chiral Weyl semimetals
• Quantum oscillations and electronic structure in the large-Chern number topological chiral semimetal PtGa
• Persistent exchange splitting in a chiral helimagnet Cr1/3NbS2
• Theoretical study of topological properties of ferromagnetic pyrite CoS${}_2$
• Multiple Dirac Nodes and Symmetry Protected Dirac Nodal Line in Orthorhombic $\alpha$-RhSi
• Spin-momentum locking from topological quantum chemistry: applications to multifold fermions
• Cubic Hall viscosity in three-dimensional topological semimetals
• Triple nodal points characterized by their nodal-line structure in all magnetic space groups
• Chiralities of nodal points along high symmetry lines with screw rotation symmetry
• Broadband optical conductivity of the chiral multifold semimetal PdGa
• Fundamental laws of chiral band crossings: local constraints, global constraints, and topological phase diagrams
• Band geometry from position-momentum duality at topological band crossings
• Chiral topological metals with multiple types of quasiparticle fermions and large spin Hall effect in the SrGePt family materials
• Strain-induced topological charge control in multifold fermion systems
• Stacking-induced Chern insulator
• Floquet topological phases with large winding number
• Analysis of the unconventional chiral fermions in a non-centrosymmetric chiral crystal $\text{PtAl}$
• Charge order induced Dirac pockets in the nonsymmorphic crystal TaTe${}_4$
• Chiral Floquet Engineering on Topological Fermions in Chiral Crystals
• Electric-field switchable chirality in rhombohedral graphene Chern insulators stabilized by tungsten diselenide
• Cubic Dirac and quadruple Weyl points in screw-symmetric materials
• Unpaired topological triply degenerate point for spin-tensor-momentum-coupled ultracold atoms
• Quantum oscillations and weak anisotropic resistivity in the chiral Fermion semimetal PdGa
• Giant Chern number of a Weyl nodal surface without upper limit
• Intrinsic Orbital Origin for the Chirality-Dependent Nonlinear Planar Hall Effect of Topological Nodal Fermions in Chiral Crystals
• Phonon helicity and Nieh-Yan Anomaly in the Kramers-Weyl semimetals of Chiral Crystals
• Polar hairs of mixed-parity nodal superconductors in Rarita-Schwinger-Weyl metals
• Transport and optical properties of the chiral semiconductor Ag3AuSe2
• Observation of pressure-induced Weyl state and superconductivity in a chirality-neutral Weyl semimetal candidate SrSi2
• Three-dimensional time reversal invariant topological superconductivity in doped chiral topological semimetals
• Magnon modes as a joint effect of surface ferromagnetism and spin-orbite coupling in CoSi chiral topological semimetal
• Correlated interaction effects in three-dimensional semi-Dirac semimetal
• Chiral separation effect for spin 3/2 fermions
• Geometric semimetals and their simulation in synthetic matter
• Surface ferromagnetism in a chiral topological semimetal CoSi
• Spinless topological chirality from Umklapp scattering in twisted 3D structures
• Discovery of nodal-line superconductivity in chiral crystals
• Coalescence of Andreev bound states on the surface of a chiral topological semimetal
• Zak Phase Dislocations in Trimer Lattices