And Su(3)-invariant Spin Chains
نویسندگان
چکیده
We formulate the thermodynamic Bethe Ansatz (TBA) equations for the closed (periodic boundary conditions) A (2) 2 quantum spin chain in an external magnetic field, in the (noncritical) regime where the anisotropy parameter η is real. In the limit η → 0, we recover the TBA equations of the antiferromagnetic su(3)-invariant chain in the fundamental representation. We solve these equations for low temperature and small field, and calculate the specific heat and magnetic susceptibility.
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