Realistic quantum critical point in one-dimensional two-impurity models

Abstract

We show that the two-impurity Anderson model exhibits an additional quantum critical point at infinitely many specific distances between both impurities for an inversion symmetric one-dimensional dispersion. Unlike the quantum critical point previously established, it is robust against particle-hole or parity symmetry breaking. The quantum critical point separates a spin doublet from a spin singlet ground state and is, therefore, protected. A finite single-particle tunneling $t$ or an applied uniform gate voltage will drive the system across the quantum critical point. The discriminative magnetic properties of the different phases cause a jump in the spectral functions at low temperature, which might be useful for future spintronics devices. A local parity conservation will prevent the spin-spin correlation function from decaying to its equilibrium value after spin manipulations.

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Cited by in corpus (7)

• Resolving Ambiguity of the Kondo Temperature Determination in Mechanically Tunable Single-Molecule Kondo Systems
• Effective low-energy description of the two impurity Anderson model: RKKY interaction and quantum criticality
• Strongly correlated multi-impurity models: The crossover from a single-impurity problem to lattice models
• Chiral numerical renormalization group
• Kondo holes in strongly correlated impurity arrays: RKKY driven Kondo screening and hole-hole interactions
• Equilibrium and real-time properties of the spin correlation function in the two-impurity Kondo model
• Spectral properties of strongly correlated multi impurity models in the Kondo insulator regime: Emergent coherence, metallic surface states and quantum phase transitions