Influence of spin fluctuations near the Mott transition: a DMFT study

Abstract

Dynamics of magnetic moments near the Mott metal-insulator transition is investigated by a combined slave-rotor and Dynamical Mean-Field Theory solution of the Hubbard model with additional fully-frustrated random Heisenberg couplings. In the paramagnetic Mott state, the spinon decomposition allows to generate a Sachdev-Ye spin liquid in place of the collection of independent local moments that typically occurs in the absence of magnetic correlations. Cooling down into the spin-liquid phase, the onset of deviations from pure Curie behavior in the spin susceptibility is found to be correlated to the temperature scale at which the Mott transition lines experience a marked bending. We also demonstrate a weakening of the effective exchange energy upon approaching the Mott boundary from the Heisenberg limit, due to quantum fluctuations associated to zero and doubly occupied sites.

6 pages, 3 figures. V3 was largely expanded

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Cited by in corpus (8)

• Sachdev-Ye-Kitaev Models and Beyond: A Window into Non-Fermi Liquids
• Linear resistivity and Sachdev-Ye-Kitaev (SYK) spin liquid behavior in a quantum critical metal with spin-$1/2$ fermions
• Linear in temperature resistivity in the limit of zero temperature from the time reparameterization soft mode
• Planckian Metal at a Doping-Induced Quantum Critical Point
• Metal-insulator transition in a random Hubbard model
• Metal-Insulator-Superconductor transition of spin-3/2 atoms on optical lattices
• Theoretical Phase diagram of unconventional alkali-doped fullerides
• Fate of spinons at the Mott point