Quantum phase transition in a gapped Anderson model: A numerical renormalization group study

Article

关键词: DILUTE MAGNETIC-ALLOYS;    STATIC PROPERTIES;    KONDO PROBLEM;    IMPURITY;    SYSTEMS;   

DOI  :  10.1103/PhysRevB.81.235106

来源: SCIE

【 摘 要 】

We use the numerical renormalization group method to investigate the spectral properties of a single-impurity Anderson model with a gap delta across the Fermi level in the conduction-electron spectrum. For any finite delta > 0, at half filling the ground state of the system is always a doublet. Away from half filling a quantum phase transition (QPT) occurs as function of the gap value delta,and the system evolves from the strong-coupling (SC) Kondo-type state, corresponding to delta delta(C). The opening of the gap leads to the formation of one (two) bound states when the system is in the SC (LM) regime. The evolution across the QPT of their positions and the corresponding weights together with the dynamic properties of the model are investigated.

【 授权许可】

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