Landau levels of Majorana fermions in a spin liquid

Abstract

Majorana fermions were originally proposed as elementary particles acting as their own antiparticles. In recent years, it has become clear that Majorana fermions can instead be realized in condensed-matter systems as emergent quasiparticles, a situation often accompanied by topological order. Here we propose a physical system which realizes Landau levels - highly degenerate single-particle states usually resulting from an orbital magnetic field acting on charged particles - for Majorana fermions. This is achieved in a variant of a quantum spin system due to Kitaev which is distorted by triaxial strain. This strained Kitaev model displays a spin-liquid phase with charge-neutral Majorana-fermion excitations whose spectrum corresponds to that of Landau levels, here arising from a tailored pseudo-magnetic field. We show that measuring the dynamic spin susceptibility reveals the Landau-level structure by a remarkable mechanism of probe-induced bound-state formation.

4+6 pages, 2+6 figures; v2: final version, Phys. Rev. Lett. (accepted)

References in corpus (8)

• Mott Insulators in the Strong Spin-Orbit Coupling Limit: From Heisenberg to a Quantum Compass and Kitaev Models
• Proximate Kitaev Quantum Spin Liquid Behaviour in α-RuCl${}_3$
• Impurity Bound States and Greens Function Zeroes as Local Signatures of Topology
• Dynamics of Fractionalization in Quantum Spin Liquids
• Quantum-Hall activation gaps in graphene
• Physical states and finite-size effects in Kitaev's honeycomb model: Bond disorder, spin excitations, and NMR lineshape
• Electronic structure of graphene hexagonal flake subjected to triaxial stress
• Spin-Peierls Instability of Three-Dimensional Spin Liquids with Majorana Fermi Surfaces

Cited by in corpus (32)

• Physics of the Kitaev model: fractionalization, dynamical correlations, and material connections
• Acoustic realization of quadrupole topological insulators
• Hunting Majorana Fermions in Kitaev Magnets
• Approximately quantized thermal Hall effect of chiral liquids coupled to phonons
• Universal sign-control of coupling in tight-binding lattices
• Dominant Kitaev interactions in the honeycomb materials Na${}_3$Co${}_2$SbO${}_6$ and Na${}_2$Co${}_2$TeO${}_6$
• Pressure-tuned magnetic interactions in honeycomb Kitaev materials
• Crystalline Kitaev spin liquids
• Interlayer Coupling Effect on a Bilayer Kitaev Model
• Pseudo-Landau levels of Bogoliubov quasiparticles in strained nodal superconductors
• Magnon Landau levels and emergent supersymmetry in strained antiferromagnets
• Phonon Hall viscosity from phonon-spinon interactions
• Majorana Landau Level Raman Spectroscopy
• Impurity bound states as detectors of topological band structures revisited
• Twist-induced magnon Landau levels in honeycomb magnets
• Magnon Landau levels in the strained antiferromagnetic honeycomb nanoribbons
• Quantum Monte Carlo study of honeycomb antiferromagnets under a triaxial strain
• Acousto-magnonic spin Hall effect in honeycomb antiferromagnets
• Bilinear Majorana representations for spin operators with spin magnitudes $S>1/2$
• Topological spinon bands and vison excitations in spin-orbit coupled quantum spin liquids
• Bound states of fractionalized excitations in a modulated Kitaev spin liquid
• Sachdev-Ye-Kitaev type physics in the strained Kitaev honeycomb model
• Deconfinement of Majorana vortex modes produces a superconducting Landau level
• Strain tuning of highly frustrated magnets: Order and disorder in the distorted kagome Heisenberg antiferromagnet
• Pseudo Landau levels, negative strain resistivity, and enhanced thermopower in twisted graphene nanoribbons
• Equivalence between vortices, twists and chiral gauge fields in Kitaev's honeycomb lattice model
• Gapless state of interacting Majorana fermions in a strain-induced Landau level
• Magnetostriction of α-RuCl3 flakes in the zigzag phase
• Real-time control of non-Abelian anyons in Kitaev spin liquid under energy dissipation
• Strain-induced Landau levels of Majorana fermions in an anisotropically interacting Kitaev model on a honeycomb lattice
• Nodal semimetals in $d\ge 3$ to sharp pseudo-Landau levels by dimensional reduction
• Anomalous enhancement of Neel order in the $S=1/2$ square lattice Heisenberg model under fictitious magnetic field