Strange metal state near a heavy-fermion quantum critical point

Abstract

Recent experiments on quantum criticality in the Ge-substituted heavy-electron material YbRh2Si2 under magnetic field have revealed a possible non-Fermi liquid (NFL) strange metal (SM) state over a finite range of fields at low temperatures, which still remains a puzzle. In the SM region, the zero-field antiferromagnetism is suppressed. Above a critical field, it gives way to a heavy Fermi liquid with Kondo correlation. The T (temperature)-linear resistivity and the T-logarithmic followed by a power-law singularity in the specific heat coefficient at low T, salient NFL behaviours in the SM region, are un-explained. We offer a mechanism to address these open issues theoretically based on the competition between a quasi-2d fluctuating short-ranged resonant- valence-bonds (RVB) spin-liquid and the Kondo correlation near criticality. Via a field-theoretical renormalization group analysis on an effective field theory beyond a large-N approach to an anti- ferromagnetic Kondo-Heisenberg model, we identify the critical point, and explain remarkably well both the crossovers and the SM behaviour.

6 pages, 3 figures and Supplementary Materials

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Cited by in corpus (5)

• Quantum phase transition in a two-dimensional Kondo-Heisenberg model: a Schwinger-boson large-N approach
• Superconductor-Metal Transition in Odd-Frequency Paired Superconductor in Magnetic Field
• Magnetic field induced quantum criticality and the Luttinger sum rule
• Is the optical conductivity of heavy fermion strange metals Planckian?
• Strange superconductivity near an antiferromagnetic heavy fermion quantum critical point