Mechanism of the insulator-to-metal transition and superconductivity in the spin liquid candidate NaYbSe${}_2$ under pressure

Abstract

The quantum spin liquid candidate NaYbSe${}_2$ was recently reported to exhibit a Mott transition under pressure. Superconductivity was observed in the high-pressure metallic phase, raising the question concerning its relation with the low-pressure quantum spin liquid ground state. Here we combine the density functional theory and the dynamical mean-field theory to explore the underlying mechanism of the insulator-to-metal transition and superconductivity and establish an overall picture of its electronic phases under pressure. Our results suggest that NaYbSe${}_2$ is a charge-transfer insulator at ambient pressure. Upon increasing pressure, however, the system first enters a semi-metallic state with incoherent Kondo scattering against coexisting localized Yb-$4f$ moments, and then turns into a heavy fermion metal. In between, there may exist a delocalization quantum critical point responsible for the observed non-Fermi liquid region with linear-in-$T$ resistivity. The insulator-to-metal transition is therefore a two-stage process. Superconductivity emerges in the heavy fermion phase with well-nested Yb-4$f$ Fermi surfaces, suggesting that spin fluctuations may play a role in the Cooper pairing. NaYbSe${}_2$ might therefore be the 3rd Yb-based heavy-fermion superconductor with a very "high" $T_c$ than most heavy fermion superconductors.

arXiv comment6 pages, 4 figures

References in corpus (34)

• Anyons in an exactly solved model and beyond
• Electronic Structure Calculations with Dynamical Mean-Field Theory: A Spectral Density Functional Approach
• Quantum Spin Liquids
• Quantum Spin Liquid States
• A continuous-time solver for quantum impurity models
• Quantum Spin Liquids
• Quantum Monte Carlo Impurity Solver for Cluster DMFT and Electronic Structure Calculations in Adjustable Base
• Dynamical Mean-Field Theory within the Full-Potential Methods: Electronic structure of Ce-115 materials
• Rare-earth triangular lattice spin liquid: a single-crystal study of YbMgGaO${}_4$
• Evidence for a spinon Fermi surface in a triangular lattice quantum spin liquid candidate
• Gapless quantum spin liquid ground state in the two-dimensional spin-1/2 triangular antiferromagnet YbMgGaO${}_4$
• Mott Transition from a Spin Liquid to a Fermi Liquid in the Spin-Frustrated Organic Conductor kappa-(ET)2Cu2(CN)3
• Quantum frustration in organic Mott insulators: from spin liquids to unconventional superconductors
• Disorder-Induced Mimicry of a Spin Liquid in YbMgGaO${}_4$
• Experimental identification of quantum spin liquids
• $\mu$SR evidence for the U(1) quantum spin liquid ground state in the triangular antiferromagnet YbMgGaO${}_4$
• Rare-earth chalcogenides: A large family of triangular lattice spin liquid candidate
• Crystalline Electric Field Randomness in the Triangular Lattice Spin-Liquid YbMgGaO${}_4$
• From high temperature supercondutivity to quantum spin liquid: progress in strong correlation physics
• An anisotropic spin model of strong spin-orbit-coupled triangular antiferromagnets
• Anisotropic field-induced ordering in the triangular-lattice quantum spin liquid NaYbSe${}_2$
• Topography of Spin Liquids on a Triangular Lattice
• Emergence of superconductivity in the canonical heavy-electron metal YbRh2Si2
• Quantum-critical phase out of frustrated magnetism in a strongly correlated metal
• Mott transition between a spin-liquid insulator and a metal in three dimensions
• Pressure-Tuned Exchange Coupling of a Quantum Spin Liquid in the Molecular Triangular Lattice $\kappa$-(ET)${}_2$Ag${}_2$(CN)${}_3$
• The Spinon Fermi Surface U(1) Spin Liquid in a Spin-Orbit-Coupled Triangular Lattice Mott Insulator YbMgGaO4
• Crystalline Electric-Field Excitations in Quantum Spin Liquids Candidate $NaYbS{e}_2$
• Mott Transition and Superconductivity in Quantum Spin Liquid Candidate NaYbSe${}_2$
• Quasi-continuous transition from a Fermi liquid to a spin liquid
• Pressure-tuned quantum criticality in the antiferromagnetic Kondo semi-metal CeNi${}_{2-\delta }$As${}_2$
• Pressure-driven collapse of the relativistic electronic ground state in a honeycomb iridate
• Nonlocal Kondo effect and quantum critical phase in heavy fermion metals
• Pressure induced metallization and possible unconventional superconductivity in spin liquid $NaYbS{e}_2$

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