Fermi surface in the absence of a Fermi liquid in the Kondo insulator SmB${}_6$

Abstract

The search for a Fermi surface in the absence of a conventional Fermi liquid has thus far yielded very few potential candidates. Among promising materials are spin-frustrated Mott insulators near the insulator-metal transition, where theory predicts a Fermi surface associated with neutral low energy excitations. Here we reveal another route to experimentally realise a Fermi surface in the absence of a Fermi liquid by the experimental study of a Kondo insulator SmB${}_6$ positioned close to the insulator-metal transition. We present experimental signatures down to low temperatures ($\ll 1$ K) associated with a Fermi surface in the bulk, including a sizeable linear specific heat coefficient, and on the application of a finite magnetic field, bulk magnetic quantum oscillations, finite quantum oscillatory entropy, and substantial enhancement in thermal conductivity well below the charge gap energy scale. Thus, the weight of evidence indicates that despite an extreme instance of Fermi liquid breakdown in Kondo insulating SmB${}_6$, a Fermi surface arises from novel itinerant low energy excitations that couple to magnetic fields, but not weak DC electric fields.

References in corpus (43)

• Topological Kondo Insulators
• Theory of Thermal Hall Effect in Quantum Magnets
• Weak magnetism and non-Fermi liquids near heavy-fermion critical points
• Fractionalized Fermi liquids
• U(1) Gauge Theory of the Hubbard Model : Spin Liquid States and Possible Application to k-(BEDT-TTF)_2 Cu_2 (CN)_3
• Low-temperature surface conduction in the Kondo insulator SmB${}_6$
• Quantum oscillations in Kondo Insulator SmB${}_6$
• Robust Surface Hall Effect and Nonlocal Transport in SmB6: Indication for an Ideal Topological Insulator
• Unconventional Fermi surface in an insulating state
• Electronic Orbital Currents and Polarization in Mott Insulators
• Hybridization, Inter-Ion Correlation, and Surface States in the Kondo Insulator SmB6
• Orbital magnetic field effects in spin liquid with spinon Fermi sea: Possible application to $\kappa$-(ET)${}_2$Cu${}_2$(CN)${}_3$
• Kondo Breakdown and Hybridization Fluctuations in the Kondo-Heisenberg Lattice
• Quantum oscillations without a Fermi surface and the anomalous de Haas-van Alphen effect
• Spin and charge dynamics of the ferromagnetic and antiferromagnetic two-dimensional half-filled Kondo lattice model
• Quantum oscillation in narrow-gap topological insulators
• Kondo Breakdown and Quantum Oscillations in SmB${}_6$
• Excitons in topological Kondo insulators - theory of thermodynamic and transport anomalies in SmB${}_6$
• Interaction Driven Subgap Spin Exciton in the Kondo Insulator SmB6
• Weak Mott insulators on the triangular lattice: possibility of a gapless nematic quantum spin liquid
• Correlation between bulk thermodynamic measurements and the low temperature resistance plateau in SmB6
• Mixed-valence insulators with neutral Fermi surfaces
• Skyrme insulators: insulators at the brink of superconductivity
• Quantum oscillations in insulators with neutral Fermi surfaces
• Transport Properties of a spinon Fermi surface coupled to a U(1) gauge field
• Transport anomalies in a simplified model for a heavy electron quantum critical point
• The Origin of Anomalous Low-Temperature Downturns in the Thermal Conductivity of Cuprates
• Anomalous 3D bulk AC conduction within the Kondo gap of SmB${}_6$ single crystals
• Large, high quality single-crystals of the new Topological Kondo Insulator, SmB6
• Chemical potential asymmetry and quantum oscillations in insulators
• Charge Friedel oscillations in a Mott insulator
• Bulk Fermi surface of charge-neutral excitations in SmB6 or not: a heat-transport study
• Majorana Fermi Sea in Insulating SmB6: A proposal and a Theory of Quantum Oscillations in Kondo Insulators
• Theory of Quantum Oscillations of Magnetization in Kondo Insulators
• Low-temperature magnetic fluctuations in the Kondo insulator SmB6
• Quantum Oscillations from Fermi Sea
• Thermal-transport studies of Two-dimensional Quantum Spin Liquids
• Fractionalized Fermi liquid on the surface of a topological Kondo insulator
• Unusual Frequency of Quantum Oscillations in Strongly Particle-Hole Asymmetric Insulators
• Puzzle maker in SmB6: accompany-type valence fluctuation state
• Global Phase Diagram and Momentum Distribution of Single-Particle Excitations in Kondo insulators
• Quantum oscillations from `open' Fermi surface in quasi-one-dimensional lattices: Application to YBa2Cu3O6 cuprates, organic salts, ladder compounds, and related systems
• The role of the short range magnetic correlations on the gap opening of the topological Kondo insulators

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• Unconventional thermal metallic state of charge-neutral fermions in an insulator
• Anomalous Quantum Oscillations in a Heterostructure of Graphene on a Proximate Quantum Spin Liquid
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• Anomalous Conductance Oscillations in the Hybridization Gap of InAs/GaSb Quantum Wells
• Quantum oscillations in strongly correlated topological Kondo insulators
• Order Fractionalization in a Kitaev-Kondo model
• Non-trivial surface states of samarium hexaboride at the (111) surface
• Field-dependent heat transport in the Kondo insulator SmB6 : phonons scattered by magnetic impurities
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• Quantum oscillations in interaction-driven insulators
• Magnetic field-tuned quantum criticality in a Kondo insulator
• Fermi surface, possible unconventional fermions, and unusually robust resistive critical fields in the chiral-structured superconductor AuBe
• Anomalous quantum oscillations and evidence for a non-trivial Berry phase in SmSb
• A highly asymmetric nodal semimetal in bulk SmB6
• Visualizing the atomic-scale origin of metallic behavior in Kondo insulators
• Exciton topology and condensation in a model quantum spin Hall insulator
• Intrinsic bulk quantum oscillations in a bulk unconventional insulator SmB${}_6$
• Cyclotron resonance inside the Mott gap: a fingerprint of emergent neutral fermions
• Metallic surface states in a correlated d-electron topological Kondo insulator candidate FeSb2
• Phonon thermal transport shaped by strong spin-phonon scattering in a Kitaev material Na${}_2$Co${}_2$TeO${}_6$
• $f$-electron hybridised metallic Fermi surface in magnetic field-induced metallic YbB${}_{12}$
• Theory of Difference Frequency Quantum Oscillations
• Quantum Oscillations in the Magnetisation and Density of States of Insulators
• Critical role of magnetic moments in heavy-fermion materials: revisiting mysteries of SmB${}_6$
• Definitive Surface Magnetotransport Study of SmB${}_6$
• Hall anomaly, Quantum Oscillations and Possible Lifshitz Transitions in Kondo Insulator YbB${}_{12}$: Evidence for Unconventional Charge Transport
• Magnetic impurities in Kondo insulators: An application to samarium hexaboride
• Diamagnetic Sm${}^{3+}$ in the topological Kondo insulator SmB${}_6$
• Luttinger sum rules and spin fractionalization in the SU(N) Kondo Lattice
• Quantum oscillations in a doped Mott insulator beyond Onsager's relation
• Low-frequency Quantum Oscillations from Interactions in Layered Metals
• Fragility of the Kondo insulating gap against disorder: relevance to recent puzzles in topological Kondo insulators
• The Fermi surface of RuO2 measured by quantum oscillations
• Bulk transport paths through defects in floating zone and Al flux grown SmB${}_6$
• Global Phase Diagram and Momentum Distribution of Single-Particle Excitations in Kondo insulators
• Charge neutral fermions and magnetic field driven instability in insulating YbIr${}_3$Si${}_7$
• Extraordinary Bulk Insulating Behavior in the Strongly Correlated Materials FeSi and FeSb${}_2$
• Shadow surface states in topological Kondo insulators
• Truncated mass divergence in a Mott metal
• Finite temperature physics of $1D$ topological Kondo insulator: Stable Haldane phase, Emergent energy scale and Beyond
• Magnetoquantum Oscillations in the Specific Heat of a Topological Kondo Insulator
• Fluctuation-dominated quantum oscillations in excitonic insulators
• Correlated Topological Mixed-Valence Insulators in Moiré Hetero-Bilayers
• Itinerant to relocalized transition of f electrons in the Kondo insulator CeRu4Sn6
• Quantum Oscillations in an Impurity-Band Anderson Insulator
• An STM perspective on hexaborides: Surface states of the Kondo insulator SmB${}_6$
• Effect of many-body interaction on de Haas-van Alphen oscillations in insulators
• Breakdown of bulk-projected isotropy in surface electronic states of topological Kondo insulator SmB${}_6$(001)
• Tunable non-Lifshitz-Kosevich temperature dependence of Shubnikov-de Haas oscillation amplitudes in SmSb
• Temperature-driven change in band structure reflecting spin-charge separation of Mott and Kondo insulators
• Emergence of electronic modes by doping Kondo insulators in the Kondo lattice and periodic Anderson models
• Universal Signatures of Majorana-like Quasiparticles in Strongly Correlated Landau-Fermi Liquids
• Magnetic effects on Chern Kondo insulator
• Low-temperature theory of inversion and quantum oscillations in Kondo insulators
• Anomalously large spin-current voltages on the surface of SmB${}_6$
• Disordered 2D ferromagnetism at the surface of FeSi
• Observation of the superconducting proximity effect from surface states in SmB${}_6$/YB${}_6$ thin film heterostructures via terahertz spectroscopy
• Persistence of correlation-driven surface states in SmB6 under pressure
• Enhancement of charge-neutral fermionic excitation near spin-flop transition\\ in magnetic Kondo material YbIr${}_3$Si${}_7$
• Inverse-current quantum electro-oscillations in a charge-density wave insulator
• Interacting fermions in narrow-gap semiconductors with band inversion
• Direct measurement of a remnant Fermi surface in SmB6
• Anomalous 4$f$ fine structure in TmSe${}_{1-x}$Te${}_x$ across the metal-insulator transition
• de Haas-van Alphen effect of correlated Dirac states in kagome metal Fe3Sn2
• On-chip quantum sensing of Kondo spins in a high-mobility quasi-one-dimensional nanoconstriction
• Theoretical investigation of quantum oscillations of specific heat in Kondo insulators
• Intrinsic one-dimensional conducting channels in the Kondo insulator SmB6