# Entanglement and boundary entropy in quantum spin chains with arbitrary direction of the boundary magnetic fields

@article{Xavier2020EntanglementAB, title={Entanglement and boundary entropy in quantum spin chains with arbitrary direction of the boundary magnetic fields}, author={J. C. Xavier and Morteza Rajabpour}, journal={Physical Review B}, year={2020} }

We calculate the entanglement and the universal boundary entropy (BE) in critical quantum spin chains, such as the transverse field Ising chain and the XXZ chain, with arbitrary direction of the boundary magnetic field (ADBMF). We determine the boundary universality class that an ADBMF induces. In particular, we show that the induced boundary conformal field theory depends on the point on the Bloch sphere where the boundary magnetic field directs. We show that the classification of the…

## One Citation

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