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Renormalized SO(5) symmetry in ladders with next-nearest-neighbor hopping

E. Arrigoni·W. Hanke
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Abstract

We study the occurrence of SO(5) symmetry in the low-energy sector of two-chain Hubbard-like systems by analyzing the flow of the running couplings ($g$-ology) under renormalization group in the weak-interaction limit. It is shown that SO(5) is asymptotically restored for low energies for rather general parameters of the bare Hamiltonian. This holds also with inclusion of a next-nearest-neighbor hopping which explicitly breaks particle-hole symmetry provided one accounts for a different single-particle weight for the quasiparticles of the two bands of the system. The physical significance of this renormalized SO(5) symmetry is discussed.

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BibTeXRIS

E. Arrigoni, W. Hanke. 1999-02-01. Renormalized SO(5) symmetry in ladders with next-nearest-neighbor hopping. https://doi.org/10.1103/physrevlett.82.2115

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