Bounds on the Mass Gap of the Ferromagnetic Xxz Chain Mass Gap of the Xxz Chain 2
نویسنده
چکیده
We prove rigorous lower and upper bounds for the mass gap of the ferromagnetic spin 1/2 XXZ chain. The two bounds coincide asymptotically in the Ising limit ! 1. Near the isotropic point, = 1, the estimates are good enough to determine the critical behaviour of the mass gap unambiguously. The derivation does not rely on exact solutions.
منابع مشابه
Bounds on the mass gap of the ferromagnetic XXZ chain
We prove rigorous lower and upper bounds for the mass gap of the ferromagnetic spin 1/2 XXZ chain. The two bounds coincide asymptotically in the Ising limit ∆ → ∞. Near the isotropic point, ∆ = 1, the estimates are good enough to determine the critical behaviour of the mass gap unambiguously. The derivation does not rely on exact solutions.
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تاریخ انتشار 1995