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Edge Magnetic Field in the xxz Spin-1/2 Chain

Ian Affleck
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Abstract

The critical behavior associated with a transverse magnetic field applied at the edge of a semi-infinite xxz S=1/2 chain is calculated using field theory techniques. Contrary to a recent claim, we find that the long-time behavior is given by a renormalization group fixed point corresponding to an infinite field which polarizes the spin at the edge. The zero temperature entropy and position-dependent magnetization are calculated.

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Ian Affleck. 1998-02-12. Edge Magnetic Field in the xxz Spin-1/2 Chain. https://doi.org/10.1088/0305-4470%2F31%2F12%2F003

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