Surface and bulk critical behaviour of theXY chain in a transverse field
نویسنده
چکیده
The surface magnetization of the quantum XY chain in a transverse field is found for arbitrary nearest neighbour interactions in closed form. This allows to derive the bulk phase diagram in a simple way. The magnetic surface behaviour and the bulk correlation length are found exactly. We consider the ferromagnetic anisotropic XY quantum chain in a transverse field with hamiltonian [1] H = − N ∑
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تاریخ انتشار 2000