Pressure-induced quantum phase transitions in topological insulator YbB6

Abstract

Topological insulators (TIs) containing 4f electrons have recently attracted intensive interests due to the possible interplay of their non-trivial topological properties and strong electronic correlations. YbB6 and SmB6 are the prototypical systems with such unusual properties, which may be tuned by external pressure to give rise to new emergent phenomena. Here, we report the first observation, through in-situ high pressure resistance, Hall, X-ray diffraction and X-ray absorption measurements, of two pressure-induced quantum phase transitions (QPTs) in YbB6. Our data revealthat the two insulating phases are separated by a metallic phase due to the pressure-driven valence change of Yb f-orbitals. In combination with previous studies, our results suggest that the two insulating states may be topologically different in nature and originate from the d-p and d-f hybridization, respectively. The tunable topological properties of YbB6 revealed in this study may shed light on the intriguing correlation between the topology and the 4f electrons from the perspective of pressure dependent studies.

18 pages, 5 figures

References in corpus (15)

• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Topological Field Theory of Time-Reversal Invariant Insulators
• Correlated Topological Insulators with Mixed Valence
• Unconventional Fermi surface in an insulating state
• Direct observation of the spin texture in strongly correlated SmB6 as evidence of the topological Kondo insulator
• Tuning bulk and surface conduction in topological Kondo insulator SmB6
• Interaction Driven Subgap Spin Exciton in the Kondo Insulator SmB6
• Exotic Kondo crossover in a wide temperature region in the topological Kondo insulator SmB6 revealed by high-resolution ARPES
• Non-Kondo-like Electronic Structure in the Correlated Rare-Earth Hexaboride YbB${}_6$
• Heavy surface state in a possible topological Kondo insulator: Magneto-thermoelectric transport on the (011)-plane of SmB${}_6$
• Composition-spread Growth and the Robust Topological Surface State of Kondo insulator SmB6 Thin Films
• Angle-resolved Photoemission Spectroscopy Study on the Surface States of the Correlated Topological Insulator YbB6
• Surface state reconstruction in ion-damaged SmB_6
• ARPES insights on the metallic states of YbB6(001): E(k) dispersion, temporal changes and spatial variation
• Surface vs bulk electronic structures of a moderately correlated topological insulator YbB6 revealed by ARPES

Cited by in corpus (13)

• Quantum phases of interacting electrons in three-dimensional dirty Dirac semimetals
• Electronic structure of YbB${}_6$: Is it a Topological Insulator or not?
• Observation of three superconducting transitions in the pressurized CDW-bearing compound TaTe2
• Collective infrared excitation in rare-earth Gd${}_x$La${}_{1-x}$B${}_6$ hexaborides
• Topologically distinct atomic insulators
• Puzzle maker in SmB6: accompany-type valence fluctuation state
• Anomalous connection between antiferromagnetic and superconducting phases in pressurized non-centrosymmetric heavy fermion compound CeRhGe3
• An STM perspective on hexaborides: Surface states of the Kondo insulator SmB${}_6$
• Quantum phase transition and destruction of Kondo effect in pressurized SmB6
• Quantum chemical insights into hexaboride electronic structures: correlations within the boron $p$-orbital subsystem
• Exploring itinerant states in divalent hexaborides using rare-earth $L$ edge resonant inelastic X-ray scattering
• Anisotropic hybridization in a new Kondo lattice compound CeCoInGa${}_3$
• Evolution of topological end states in the one-dimensional Kondo-Heisenberg model with site modulation